diff --git a/.gitignore b/.gitignore
index 7e36cd5..92e065b 100644
--- a/.gitignore
+++ b/.gitignore
@@ -363,4 +363,5 @@ gradle-app.setting
 
 # End of https://www.toptal.com/developers/gitignore/api/windows,macos,git,java,maven,eclipse,intellij,gradle,netbeans,visualstudiocode
 
-application.yaml
\ No newline at end of file
+application.yaml
+env.properties
\ No newline at end of file
diff --git a/build.gradle b/build.gradle
index 37bb98c..57ef77d 100644
--- a/build.gradle
+++ b/build.gradle
@@ -31,10 +31,21 @@ dependencies {
 	compileOnly 'org.projectlombok:lombok'
 	//runtimeOnly 'com.mysql:mysql-connector-j'
 
+	// h2
+	implementation 'com.h2database:h2'
+
 	// validation
 	implementation 'jakarta.validation:jakarta.validation-api:3.0.2'
 	implementation 'org.hibernate.validator:hibernate-validator:8.0.1.Final'
 
+	// spring security
+	implementation 'org.springframework.boot:spring-boot-starter-security'
+	implementation 'org.thymeleaf.extras:thymeleaf-extras-springsecurity6'
+
+	// java mail sender
+	implementation 'org.springframework.boot:spring-boot-starter-mail'
+
+	compileOnly 'org.projectlombok:lombok'
 	annotationProcessor 'org.projectlombok:lombok'
 	testImplementation 'org.springframework.boot:spring-boot-starter-test'
 	testRuntimeOnly 'org.junit.platform:junit-platform-launcher'
diff --git a/src/main/java/apptive/devlog/auth/controller/UserController.java b/src/main/java/apptive/devlog/auth/controller/UserController.java
index 4ea48e7..7d476d5 100644
--- a/src/main/java/apptive/devlog/auth/controller/UserController.java
+++ b/src/main/java/apptive/devlog/auth/controller/UserController.java
@@ -5,12 +5,14 @@
 import apptive.devlog.auth.dto.UserSaveForm;
 import apptive.devlog.auth.entity.User;
 import apptive.devlog.auth.service.UserService;
-import apptive.devlog.auth.session.SessionConst;
 import jakarta.servlet.http.HttpServletRequest;
 import jakarta.servlet.http.HttpSession;
 import lombok.RequiredArgsConstructor;
 import lombok.extern.slf4j.Slf4j;
+import org.springframework.security.core.annotation.AuthenticationPrincipal;
+import org.springframework.security.core.userdetails.UserDetails;
 import org.springframework.stereotype.Controller;
+import org.springframework.transaction.annotation.Transactional;
 import org.springframework.ui.Model;
 import org.springframework.validation.BindingResult;
 import org.springframework.validation.annotation.Validated;
@@ -23,112 +25,62 @@
 public class UserController {
     private final UserService userService;
 
-    /**
-     * login 진입 페이지
-     * @param model
-     * @return
-     */
+    // 로그인 시 진입하는 user home
     @GetMapping
-    public String loginHome(@SessionAttribute(name = SessionConst.LOGIN_USER, required = false) UserLoginForm loginUser, Model model){
-
-        // 세션 정보가 있으면 유저 정보 표기
-        if(loginUser == null){
-            return "users/home";
-        }
-        else{
-            model.addAttribute("userLoginForm", loginUser);
-            return "users/userHome";
-        }
+    public String loginHome(@AuthenticationPrincipal UserDetails userDetails, Model model){
+        model.addAttribute("user", userDetails);
+        return "users/userHome";
     }
 
-    /**
-     *
-     * @param model
-     * @return
-     */
+    // 회원가입
     @GetMapping("/signup")
-    public String signupForm(Model model){
-        model.addAttribute("user", new User());
+    public String signupForm(Model model) {
+        model.addAttribute("user", new UserSaveForm());
         return "users/signup";
     }
 
-    /**
-     *
-     * @param form
-     * @param bindingResult
-     * @return
-     */
     @PostMapping("/signup")
     public String signup(@Validated @ModelAttribute("user") UserSaveForm form, BindingResult bindingResult){
-        // 이메일 중복 체크
-        if(form.getEmail() != null){
-            if(userService.isEmailDuplicated(form.getEmail())){
-                bindingResult.rejectValue("email", "duplicated", "이미 가입된 이메일입니다.");
-            }
-        }
-
-        // 닉네임 중복 체크
-        if(form.getNickname() != null){
-            if(userService.isNicknameDuplicated(form.getNickname())){
-                bindingResult.rejectValue("nickname", "duplicated", "이미 사용 중인 닉네임입니다.");
-            }
-        }
-
-        // Validation
-        if(bindingResult.hasErrors()){
+        if(bindingResult.hasErrors()) {
             log.info("errors = {}", bindingResult);
 
-            return "/users/home";
+            return "users/signup";
         }
 
-        // 성공 로직
-        User user = new User(form);
+        User user = new User();
+        user.setEmail(form.getEmail());
+        user.setPassword(form.getPassword());
+        user.setName(form.getName());
+        user.setNickname(form.getNickname());
+        user.setBirth(form.getBirth());
+        user.setGender(form.getGender());
         userService.signup(user);
 
         return "redirect:/users/home";
     }
 
-    /**
-     *
-     * @param model
-     * @return
-     */
+    // 로그인
     @GetMapping("/login")
     public String loginForm(Model model){
-        model.addAttribute(new User());
+        model.addAttribute("user", new UserLoginForm());
 
         return "users/login";
     }
 
-    /**
-     *
-     * @param form
-     * @param bindingResult
-     * @return
-     */
     @PostMapping("/login")
-    public String login(@Validated @ModelAttribute("user") UserLoginForm form, BindingResult bindingResult, HttpServletRequest request){
-        // 1차 유효성 검사
-        if(bindingResult.hasErrors()){
+    public String login(@Validated @ModelAttribute("user") UserLoginForm form, BindingResult bindingResult) {
+        if (bindingResult.hasErrors()) {
             log.info("errors = {}", bindingResult);
 
             return "users/login";
         }
 
-        // 로그인 처리
-        HttpSession session = request.getSession();
-        session.setAttribute(SessionConst.LOGIN_USER, form);
-
         return "redirect:/main";
     }
 
+    // 로그아웃
     @PostMapping("/logout")
     public String logout(HttpServletRequest request){
-        HttpSession session = request.getSession(false);
-
-        if(session != null){
-            session.invalidate();
-        }
         return "redirect:/main";
     }
 }
diff --git a/src/main/java/apptive/devlog/auth/dto/UserLoginForm.java b/src/main/java/apptive/devlog/auth/dto/UserLoginForm.java
index 2de9fca..33a3289 100644
--- a/src/main/java/apptive/devlog/auth/dto/UserLoginForm.java
+++ b/src/main/java/apptive/devlog/auth/dto/UserLoginForm.java
@@ -7,6 +7,7 @@
 @Data
 public class UserLoginForm {
 
+    @NotBlank(message = "이메일은 필수입니다.")
     @Email(message = "이메일 형식이 아닙니다.")
     private String email;
     @NotBlank
diff --git a/src/main/java/apptive/devlog/auth/entity/User.java b/src/main/java/apptive/devlog/auth/entity/User.java
index 4d178f9..c23db82 100644
--- a/src/main/java/apptive/devlog/auth/entity/User.java
+++ b/src/main/java/apptive/devlog/auth/entity/User.java
@@ -10,6 +10,8 @@
 import java.time.LocalDateTime;
 
 @Entity
+// springSecurity user 인증 정보와 테이블 겹쳐서 수정
+@Table(name = "users")
 @Getter @Setter
 public class User {
 
@@ -34,30 +36,26 @@ public class User {
 
     private Gender gender;
 
+    @Column(nullable = true)
+    private String role;
+
     public User() {}
 
-    public User(String email, String password, String name, String nickname, LocalDate birth, Gender gender){
+    public User(String email, String password, String name, String nickname, LocalDate birth, Gender gender, String role){
         this.email = email;
         this.password = password;
         this.name = name;
         this.nickname = nickname;
         this.birth = birth;
         this.gender = gender;
+        this.role = role;
     }
 
-    // 생성자 필요서 다시 생각해보기
-    public User(UserLoginForm form){
-        this.email = form.getEmail();
-        this.password = form.getPassword();
-    }
-
-    public User(UserSaveForm form){
-        this.email = form.getEmail();
-        this.password = form.getPassword();
-        this.name = form.getName();
-        this.nickname = form.getNickname();
-        this.birth = form.getBirth();
-        this.gender = form.getGender();
+    // role 기본 값 설정
+    @PrePersist
+    public void prePersist() {
+        if (this.role == null) {
+            this.role = "user";
+        }
     }
-
 }
diff --git a/src/main/java/apptive/devlog/auth/repository/UserRepository.java b/src/main/java/apptive/devlog/auth/repository/UserRepository.java
index 0127d9f..28d7987 100644
--- a/src/main/java/apptive/devlog/auth/repository/UserRepository.java
+++ b/src/main/java/apptive/devlog/auth/repository/UserRepository.java
@@ -7,4 +7,9 @@
 
 public interface UserRepository extends JpaRepository<User, Long> {
     Optional<User> findByEmail(String email);
+    Optional<User> findByName(String name);
+
+    boolean existsByEmail(String email);
+
+    boolean existsByNickname(String nickname);
 }
diff --git a/src/main/java/apptive/devlog/auth/service/UserService.java b/src/main/java/apptive/devlog/auth/service/UserService.java
index c79c0ec..719eb3c 100644
--- a/src/main/java/apptive/devlog/auth/service/UserService.java
+++ b/src/main/java/apptive/devlog/auth/service/UserService.java
@@ -4,32 +4,56 @@
 import apptive.devlog.auth.repository.UserRepository;
 import lombok.RequiredArgsConstructor;
 import org.springframework.stereotype.Service;
+import org.springframework.transaction.annotation.Transactional;
+
+import java.util.NoSuchElementException;
+import java.util.Optional;
 
 @Service
+@Transactional
 @RequiredArgsConstructor
 public class UserService {
 
     private final UserRepository userRepository;
 
     public User signup(User user){
+        // 서비스에서 exception throw
+        if(isEmailDuplicated(user.getEmail())){
+            throw new IllegalArgumentException("중복된 이메일입니다.");
+        }
+        if(isNicknameDuplicated(user.getNickname())){
+            throw new IllegalArgumentException("중복된 닉네임입니다.");
+        }
+
         return userRepository.save(user);
     }
 
+    //로그인
     public User login(String email, String password){
         return userRepository.findByEmail(email)
-                .filter(m->m.getPassword().equals(password))
+                .filter(m -> m.getPassword().equals(password))
                 .orElse(null);
     }
 
+    // 이메일 중복 체크
     public boolean isEmailDuplicated(String email){
-        // 중복 체크
-
-        return false;
+        // 중복 체크 처리
+        return userRepository.existsByEmail(email);
     }
 
+    // 닉네임 중복 체크
     public boolean isNicknameDuplicated(String nickname){
-        // 중복 체크
+        return userRepository.existsByNickname(nickname);
+    }
+
+    public User getUser(String name){
+        Optional<User> user = userRepository.findByName(name);
 
-        return false;
+        if(user.isEmpty()){
+            throw new NoSuchElementException("해당 사용자는 존재하지 않습니다.");
+        }
+        else{
+            return user.get();
+        }
     }
 }
diff --git a/src/main/java/apptive/devlog/auth/session/SessionConst.java b/src/main/java/apptive/devlog/auth/session/SessionConst.java
deleted file mode 100644
index 8415296..0000000
--- a/src/main/java/apptive/devlog/auth/session/SessionConst.java
+++ /dev/null
@@ -1,5 +0,0 @@
-package apptive.devlog.auth.session;
-
-public class SessionConst {
-    public static final String LOGIN_USER = "loginUser";
-}
diff --git a/src/main/java/apptive/devlog/board/controller/BoardController.java b/src/main/java/apptive/devlog/board/controller/BoardController.java
new file mode 100644
index 0000000..b62a900
--- /dev/null
+++ b/src/main/java/apptive/devlog/board/controller/BoardController.java
@@ -0,0 +1,90 @@
+package apptive.devlog.board.controller;
+
+import apptive.devlog.auth.entity.User;
+import apptive.devlog.auth.service.UserService;
+import apptive.devlog.board.entity.Comment;
+import apptive.devlog.board.entity.Post;
+import apptive.devlog.board.service.CommentService;
+import apptive.devlog.board.service.PostService;
+import apptive.devlog.board.service.ReplyService;
+import apptive.devlog.mail.controller.MailController;
+import apptive.devlog.mail.service.MailService;
+import jakarta.servlet.http.HttpServletRequest;
+import lombok.RequiredArgsConstructor;
+import org.springframework.http.HttpStatus;
+import org.springframework.http.ResponseEntity;
+import org.springframework.security.core.annotation.AuthenticationPrincipal;
+import org.springframework.security.core.userdetails.UserDetails;
+import org.springframework.web.bind.annotation.*;
+
+import java.util.List;
+import java.util.Optional;
+
+@RestController
+@RequestMapping("/api/board")
+@RequiredArgsConstructor
+public class BoardController {
+    private final PostService postService;
+    private final CommentService commentService;
+    private final ReplyService replyService;
+    private final MailService mailService;
+    private final UserService userService;
+
+    // 게시물 생성
+    @PostMapping("/posts")
+    public ResponseEntity<Post> createPost(@RequestBody Post post, HttpServletRequest request) {
+        // 게시물 생성
+        Post createdPost = postService.create(post);
+        return ResponseEntity.status(HttpStatus.CREATED).body(createdPost); // 201
+    }
+
+    // 게시물 조회
+    @GetMapping("/posts/{id}")
+    public ResponseEntity<Post> getPost(@PathVariable Long id){
+        Post post = postService.get(id);
+        return ResponseEntity.ok(post); // 200
+    }
+
+    // 유효한 게시물 목록 조회
+    @GetMapping("/posts")
+    public ResponseEntity<List<Post>> getAllPosts() {
+        List<Post> posts = postService.getNotDeleted();
+        return ResponseEntity.ok(posts); // 200
+    }
+
+    // 게시물 수정
+    @PutMapping("/posts/{id}")
+    public ResponseEntity<Post> updatePost(@PathVariable Long id, @RequestBody Post updatedPost){
+        Post post = postService.update(id, updatedPost);
+        return ResponseEntity.ok(post); // 200
+    }
+
+    // 게시물 삭제
+    @DeleteMapping("/posts/{id}")
+    public ResponseEntity<Void> deletePost(@PathVariable Long id){
+        postService.delete(id);
+        return ResponseEntity.noContent().build(); // 200
+    }
+
+    // 댓글 생성
+    @PostMapping("/posts/{postId}/comments")
+    public ResponseEntity<Comment> createComment(@PathVariable Long postId, @RequestBody Comment comment){
+        // 게시물에 댓글 연결 후 댓글 알림
+        Comment createdComment = commentService.createAndNotify(postId, comment);
+        return ResponseEntity.status(HttpStatus.CREATED).body(createdComment); // 201
+    }
+
+    // 게시물 댓글 목록 조회
+
+    // commentService.getValidCommentByPostId() 사용
+    @GetMapping("/posts/{postId}/comments")
+    public ResponseEntity<List<Comment>> getCommentsForPost(@PathVariable Long postId) {
+        List<Comment> comments = commentService.getValidCommentByPostId(postId);
+        if(comments.isEmpty()) {
+            return ResponseEntity.noContent().build(); // 404
+        }
+
+        return ResponseEntity.ok(comments); // 200 ok
+    }
+
+}
diff --git a/src/main/java/apptive/devlog/board/entity/Comment.java b/src/main/java/apptive/devlog/board/entity/Comment.java
index f23d12e..991d7e0 100644
--- a/src/main/java/apptive/devlog/board/entity/Comment.java
+++ b/src/main/java/apptive/devlog/board/entity/Comment.java
@@ -1,19 +1,33 @@
 package apptive.devlog.board.entity;
 
+import apptive.devlog.auth.entity.User;
 import jakarta.persistence.*;
+import lombok.Getter;
+import lombok.Setter;
 
 import java.time.LocalDate;
+import java.util.List;
 
 @Entity
+@Getter @Setter
 public class Comment {
     @Id
     @GeneratedValue(strategy = GenerationType.IDENTITY)
     private Long id;
-    private Long userId;
-    //post foreign key
-    private Long postId;
+
+    @ManyToOne
+    @JoinColumn(name = "user_id")
+    private User user;
+
+    @ManyToOne
+    @JoinColumn(name = "post_id")
+    private Post post;
+
     private LocalDate createdAt;
     private LocalDate updatedAt;
     private Long likeCount;
     private Boolean isDeleted;
+
+    @OneToMany(mappedBy = "comment", cascade = CascadeType.ALL)
+    private List<Reply> replyList;
 }
diff --git a/src/main/java/apptive/devlog/board/entity/Post.java b/src/main/java/apptive/devlog/board/entity/Post.java
index 87c435f..4f57e8f 100644
--- a/src/main/java/apptive/devlog/board/entity/Post.java
+++ b/src/main/java/apptive/devlog/board/entity/Post.java
@@ -1,10 +1,12 @@
 package apptive.devlog.board.entity;
 
+import apptive.devlog.auth.entity.User;
 import jakarta.persistence.*;
 import lombok.Getter;
 import lombok.Setter;
 
 import java.time.LocalDate;
+import java.util.List;
 
 @Entity
 @Getter @Setter
@@ -12,13 +14,20 @@ public class Post {
     @Id
     @GeneratedValue(strategy = GenerationType.IDENTITY)
     private Long id;
-    private Long userId;
-    //postData foreign key
-    private Long dataId;
+
+    @ManyToOne
+    @JoinColumn(name = "user_id")
+    private User user;
+
+    @OneToOne
+    @JoinColumn(name = "postData_id")
+    private PostData postData;
 
     private LocalDate createdAt;
     private LocalDate updatedAt;
     private Long likeCount;
     private Boolean isDeleted;
 
+    @OneToMany(mappedBy = "post", cascade = CascadeType.ALL)
+    private List<Comment> commentList;
 }
diff --git a/src/main/java/apptive/devlog/board/entity/PostData.java b/src/main/java/apptive/devlog/board/entity/PostData.java
index 161db25..d8cce2e 100644
--- a/src/main/java/apptive/devlog/board/entity/PostData.java
+++ b/src/main/java/apptive/devlog/board/entity/PostData.java
@@ -7,8 +7,6 @@
 import lombok.Getter;
 import lombok.Setter;
 
-import java.time.LocalDate;
-
 @Entity
 @Getter @Setter
 public class PostData {
diff --git a/src/main/java/apptive/devlog/board/entity/Reply.java b/src/main/java/apptive/devlog/board/entity/Reply.java
index bb4ae25..25c627d 100644
--- a/src/main/java/apptive/devlog/board/entity/Reply.java
+++ b/src/main/java/apptive/devlog/board/entity/Reply.java
@@ -1,24 +1,31 @@
 package apptive.devlog.board.entity;
 
-import jakarta.persistence.Entity;
-import jakarta.persistence.GeneratedValue;
-import jakarta.persistence.GenerationType;
-import jakarta.persistence.Id;
+import apptive.devlog.auth.entity.User;
+import jakarta.persistence.*;
+import lombok.Getter;
+import lombok.Setter;
 
 import java.time.LocalDate;
 
 @Entity
+@Getter @Setter
 public class Reply {
     @Id
     @GeneratedValue(strategy = GenerationType.IDENTITY)
     private Long id;
 
-    private Long userId;
-    //comment foreign key
-    private Long commentId;
+    @ManyToOne
+    @JoinColumn(name = "user_id")
+    private User user;
+
+    @ManyToOne
+    @JoinColumn(name = "comment_id")
+    private Comment comment;
 
     private LocalDate createdAt;
     private LocalDate updatedAt;
     private Long likeCount;
     private Boolean isDeleted;
+
+
 }
diff --git a/src/main/java/apptive/devlog/board/repository/CommentRepository.java b/src/main/java/apptive/devlog/board/repository/CommentRepository.java
new file mode 100644
index 0000000..f760b88
--- /dev/null
+++ b/src/main/java/apptive/devlog/board/repository/CommentRepository.java
@@ -0,0 +1,15 @@
+package apptive.devlog.board.repository;
+
+import apptive.devlog.board.entity.Comment;
+import org.springframework.data.jpa.repository.JpaRepository;
+import org.springframework.data.jpa.repository.Query;
+import org.springframework.data.repository.query.Param;
+
+import java.util.List;
+
+public interface CommentRepository extends JpaRepository<Comment, Long> {
+    List<Comment> findByIsDeletedFalse();
+
+    @Query("SELECT c From Comment c Where c.post.id = :postId AND c.isDeleted = false")
+    List<Comment> findValidByPostId(@Param("postId") Long postId);
+}
diff --git a/src/main/java/apptive/devlog/board/repository/PostDataRepository.java b/src/main/java/apptive/devlog/board/repository/PostDataRepository.java
new file mode 100644
index 0000000..1b185cb
--- /dev/null
+++ b/src/main/java/apptive/devlog/board/repository/PostDataRepository.java
@@ -0,0 +1,11 @@
+package apptive.devlog.board.repository;
+
+import apptive.devlog.auth.entity.User;
+import apptive.devlog.board.entity.PostData;
+import org.springframework.data.jpa.repository.JpaRepository;
+
+import java.util.List;
+import java.util.Optional;
+
+public interface PostDataRepository extends JpaRepository<PostData, Long> {
+}
diff --git a/src/main/java/apptive/devlog/board/repository/PostRepository.java b/src/main/java/apptive/devlog/board/repository/PostRepository.java
new file mode 100644
index 0000000..ecc1f65
--- /dev/null
+++ b/src/main/java/apptive/devlog/board/repository/PostRepository.java
@@ -0,0 +1,12 @@
+package apptive.devlog.board.repository;
+
+import apptive.devlog.auth.entity.User;
+import apptive.devlog.board.entity.Post;
+import org.springframework.data.jpa.repository.JpaRepository;
+
+import java.util.List;
+
+public interface PostRepository extends JpaRepository<Post, Long> {
+    List<Post> findByIsDeletedFalse();
+    List<Post> findByUserId(Long userId);
+}
diff --git a/src/main/java/apptive/devlog/board/repository/ReplyRepository.java b/src/main/java/apptive/devlog/board/repository/ReplyRepository.java
new file mode 100644
index 0000000..7c037aa
--- /dev/null
+++ b/src/main/java/apptive/devlog/board/repository/ReplyRepository.java
@@ -0,0 +1,10 @@
+package apptive.devlog.board.repository;
+
+import apptive.devlog.board.entity.Reply;
+import org.springframework.data.jpa.repository.JpaRepository;
+
+import java.util.List;
+
+public interface ReplyRepository extends JpaRepository<Reply, Long> {
+    List<Reply> findByCommentId(Long commentId);
+}
diff --git a/src/main/java/apptive/devlog/board/service/CommentService.java b/src/main/java/apptive/devlog/board/service/CommentService.java
new file mode 100644
index 0000000..90d5b09
--- /dev/null
+++ b/src/main/java/apptive/devlog/board/service/CommentService.java
@@ -0,0 +1,81 @@
+package apptive.devlog.board.service;
+
+import apptive.devlog.board.entity.Comment;
+import apptive.devlog.board.entity.Post;
+import apptive.devlog.board.repository.CommentRepository;
+import apptive.devlog.board.repository.PostRepository;
+import apptive.devlog.mail.service.MailService;
+import jakarta.persistence.EntityNotFoundException;
+import lombok.RequiredArgsConstructor;
+import org.springframework.stereotype.Service;
+
+import java.time.LocalDate;
+import java.util.List;
+
+@Service
+@RequiredArgsConstructor
+public class CommentService {
+    private final CommentRepository commentRepository;
+    private final PostService postService;
+    private final MailService mailService;
+
+    // 댓글 생성, 이메일 notify
+    public Comment createAndNotify(Long postId, Comment comment){
+        Post post = postService.get(postId);
+        comment.setPost(post);
+
+        comment.setCreatedAt(LocalDate.now());
+        comment.setUpdatedAt(LocalDate.now());
+        comment.setIsDeleted(false);
+        comment.setLikeCount(0L);
+
+        Comment savedComment = commentRepository.save(comment);
+
+        //이메일 전송
+        mailService.sendMimeMessage(post.getUser().getEmail());
+
+        return savedComment;
+    }
+
+    // 수정
+    public Comment update(Long id, Comment updated){
+        Comment comment = commentRepository.findById(id).orElseThrow(
+                () -> new EntityNotFoundException("해당 댓글을 찾을 수 없습니다.")
+        );
+        comment.setUpdatedAt(LocalDate.now());
+        comment.setIsDeleted(updated.getIsDeleted());
+        comment.setLikeCount(updated.getLikeCount());
+        return commentRepository.save(comment);
+    }
+
+    // 삭제 - soft delete
+    public void delete(Long id){
+        Comment comment = commentRepository.findById(id).orElseThrow(
+                () -> new EntityNotFoundException("해당 댓글을 찾을 수 없습니다.")
+        );
+        comment.setIsDeleted(true);
+        commentRepository.save(comment);
+    }
+
+    // 단일 조회. 삭제 요소도 조회 가능
+    public Comment get(Long id){
+        return commentRepository.findById(id).orElseThrow(
+                () -> new EntityNotFoundException("해당 댓글을 찾을 수 없습니다.")
+        );
+    }
+
+
+    // 작성된 모든 댓글 조회
+    public List<Comment> getAll(){
+        return commentRepository.findAll();
+    }
+
+    // 유효한 댓글만 조회
+    public List<Comment> getNotDeleted(){
+        return commentRepository.findByIsDeletedFalse();
+    }
+
+    public List<Comment> getValidCommentByPostId(Long postId){
+        return commentRepository.findValidByPostId(postId);
+    }
+}
diff --git a/src/main/java/apptive/devlog/board/service/PostDataService.java b/src/main/java/apptive/devlog/board/service/PostDataService.java
new file mode 100644
index 0000000..6f6be04
--- /dev/null
+++ b/src/main/java/apptive/devlog/board/service/PostDataService.java
@@ -0,0 +1,45 @@
+package apptive.devlog.board.service;
+
+import apptive.devlog.board.entity.PostData;
+import apptive.devlog.board.repository.PostDataRepository;
+import jakarta.persistence.EntityNotFoundException;
+import lombok.RequiredArgsConstructor;
+import org.springframework.stereotype.Service;
+
+import java.util.List;
+
+@Service
+@RequiredArgsConstructor
+public class PostDataService {
+    private final PostDataRepository postDataRepository;
+
+    public PostData create(PostData data) {
+        return postDataRepository.save(data);
+    }
+
+    public PostData update(Long id, PostData updated) {
+        PostData data = postDataRepository.findById(id).orElseThrow(
+                () -> new EntityNotFoundException("해당 게시글을 찾을 수 없습니다.")
+        );
+        data.setTitle(updated.getTitle());
+        data.setContent(updated.getContent());
+        return postDataRepository.save(data);
+    }
+
+    // 삭제 - soft delete
+    public void delete(Long id) {
+        postDataRepository.deleteById(id);
+    }
+
+    // 단일 조회. 삭제 요소도 조회 가능
+    public PostData get(Long id) {
+        return postDataRepository.findById(id).orElseThrow(
+                () -> new EntityNotFoundException("해당 게시글을 찾을 수 없습니다.")
+        );
+    }
+
+    // 모든 데이터 조회
+    public List<PostData> getAll() {
+        return postDataRepository.findAll();
+    }
+}
diff --git a/src/main/java/apptive/devlog/board/service/PostService.java b/src/main/java/apptive/devlog/board/service/PostService.java
new file mode 100644
index 0000000..7ca8354
--- /dev/null
+++ b/src/main/java/apptive/devlog/board/service/PostService.java
@@ -0,0 +1,72 @@
+package apptive.devlog.board.service;
+
+import apptive.devlog.auth.entity.User;
+import apptive.devlog.auth.repository.UserRepository;
+import apptive.devlog.board.entity.Post;
+import apptive.devlog.board.entity.PostData;
+import apptive.devlog.board.repository.PostDataRepository;
+import apptive.devlog.board.repository.PostRepository;
+import jakarta.persistence.EntityNotFoundException;
+import lombok.RequiredArgsConstructor;
+import org.springframework.stereotype.Service;
+
+import java.time.LocalDate;
+import java.util.List;
+
+@Service
+@RequiredArgsConstructor
+public class PostService {
+    private final PostRepository postRepository;
+
+    // 생성 후 이메일 전송
+    public Post create(Post post){
+        post.setCreatedAt(LocalDate.now());
+        post.setUpdatedAt(LocalDate.now());
+        post.setIsDeleted(false);
+        post.setLikeCount(0L);
+
+        return postRepository.save(post);
+    }
+
+    // 수정
+    public Post update(Long id, Post updated){
+        Post post = postRepository.findById(id).orElseThrow(
+                () -> new EntityNotFoundException("해당 게시글을 찾을 수 없습니다."));
+        post.setUpdatedAt(LocalDate.now());
+        post.setLikeCount(updated.getLikeCount());
+        post.setIsDeleted(updated.getIsDeleted());
+        return postRepository.save(post);
+    }
+
+    // 삭제 - soft delete
+    public void delete(Long id) {
+        Post post = postRepository.findById(id).orElseThrow(
+                () -> new EntityNotFoundException("해당 게시글을 찾을 수 없습니다.")
+        );
+        post.setIsDeleted(true);
+        postRepository.save(post);
+    }
+
+    // 단일 조회. 삭제 요소도 조회 가능
+    public Post get(Long id){
+        return postRepository.findById(id).orElseThrow(
+                () -> new EntityNotFoundException("해당 게시글을 찾을 수 없습니다."));
+    }
+
+    public User getUserById(Long id){
+        Post post = postRepository.findById(id).orElseThrow(
+                () -> new EntityNotFoundException("해당 게시글을 찾을 수 없습니다.")
+        );
+        return post.getUser();
+    }
+
+    //모든 게시글 조회
+    public List<Post> getAll() {
+        return postRepository.findAll();
+    }
+
+    // 유효한 게시글만 조회
+    public List<Post> getNotDeleted() {
+        return postRepository.findByIsDeletedFalse();
+    }
+}
diff --git a/src/main/java/apptive/devlog/board/service/ReplyService.java b/src/main/java/apptive/devlog/board/service/ReplyService.java
new file mode 100644
index 0000000..3b5623c
--- /dev/null
+++ b/src/main/java/apptive/devlog/board/service/ReplyService.java
@@ -0,0 +1,50 @@
+package apptive.devlog.board.service;
+
+import apptive.devlog.board.entity.Reply;
+import apptive.devlog.board.repository.ReplyRepository;
+import jakarta.persistence.EntityNotFoundException;
+import lombok.RequiredArgsConstructor;
+import org.springframework.stereotype.Service;
+
+import java.time.LocalDate;
+
+@Service
+@RequiredArgsConstructor
+public class ReplyService {
+    private final ReplyRepository replyRepository;
+
+    public Reply create(Reply reply){
+        reply.setCreatedAt(LocalDate.now());
+        reply.setCreatedAt(LocalDate.now());
+        reply.setIsDeleted(false);
+        reply.setLikeCount(0L);
+
+        return replyRepository.save(reply);
+    }
+
+    public Reply update(Long id, Reply updated) {
+        Reply reply = replyRepository.findById(id).orElseThrow(
+                () -> new EntityNotFoundException("해당 답글을 찾을 수 없습니다.")
+        );
+        reply.setUpdatedAt(LocalDate.now());
+        reply.setLikeCount(updated.getLikeCount());
+        reply.setIsDeleted(updated.getIsDeleted());
+        return replyRepository.save(reply);
+    }
+
+    // 삭제 - soft delete
+    public void delete(Long id) {
+        Reply reply = replyRepository.findById(id).orElseThrow(
+                () -> new EntityNotFoundException("해당 답글을 찾을 수 없습니다.")
+        );
+
+        reply.setIsDeleted(true);
+        replyRepository.save(reply);
+    }
+
+    public Reply get(Long id){
+        return replyRepository.findById(id).orElseThrow(
+                () -> new EntityNotFoundException("해당 게시글을 찾을 수 없습니다."));
+    }
+
+}
diff --git a/src/main/java/apptive/devlog/config/CustomUserDetails.java b/src/main/java/apptive/devlog/config/CustomUserDetails.java
new file mode 100644
index 0000000..61824a1
--- /dev/null
+++ b/src/main/java/apptive/devlog/config/CustomUserDetails.java
@@ -0,0 +1,40 @@
+package apptive.devlog.config;
+
+import apptive.devlog.auth.entity.User;
+import org.springframework.security.core.GrantedAuthority;
+import org.springframework.security.core.authority.SimpleGrantedAuthority;
+import org.springframework.security.core.userdetails.UserDetails;
+
+import java.util.Collection;
+import java.util.List;
+
+public class CustomUserDetails implements UserDetails {
+
+    private final User user;
+
+    public CustomUserDetails(User user) {
+        this.user = user;
+    }
+
+    @Override
+    public Collection<? extends GrantedAuthority> getAuthorities() {
+        return List.of(new SimpleGrantedAuthority("ROLE_" + user.getRole()));
+    }
+
+    @Override
+    public String getPassword() {
+        return user.getPassword();
+    }
+
+    @Override
+    public String getUsername() {
+        // username 대신 email 사용
+        return user.getEmail();
+    }
+
+    // 나머지는 기본적으로 true로 설정
+    @Override public boolean isAccountNonExpired() {return true;}
+    @Override public boolean isAccountNonLocked() {return true;}
+    @Override public boolean isCredentialsNonExpired() {return true;}
+    @Override public boolean isEnabled() {return true;}
+}
diff --git a/src/main/java/apptive/devlog/config/CustomUserDetailsService.java b/src/main/java/apptive/devlog/config/CustomUserDetailsService.java
new file mode 100644
index 0000000..daf18da
--- /dev/null
+++ b/src/main/java/apptive/devlog/config/CustomUserDetailsService.java
@@ -0,0 +1,23 @@
+package apptive.devlog.config;
+
+import apptive.devlog.auth.entity.User;
+import apptive.devlog.auth.repository.UserRepository;
+import lombok.RequiredArgsConstructor;
+import org.springframework.security.core.userdetails.UserDetails;
+import org.springframework.security.core.userdetails.UserDetailsService;
+import org.springframework.security.core.userdetails.UsernameNotFoundException;
+import org.springframework.stereotype.Service;
+
+@Service
+@RequiredArgsConstructor
+public class CustomUserDetailsService implements UserDetailsService {
+
+    private final UserRepository userRepository;
+
+    @Override
+    public UserDetails loadUserByUsername(String email) throws UsernameNotFoundException{
+        User user = userRepository.findByEmail(email)
+                .orElseThrow(() -> new UsernameNotFoundException("사용자를 찾을 수 없습니다."));
+        return new CustomUserDetails(user);
+    }
+}
diff --git a/src/main/java/apptive/devlog/config/MailConfig.java b/src/main/java/apptive/devlog/config/MailConfig.java
new file mode 100644
index 0000000..82ac2a8
--- /dev/null
+++ b/src/main/java/apptive/devlog/config/MailConfig.java
@@ -0,0 +1,9 @@
+package apptive.devlog.config;
+
+import org.springframework.context.annotation.Configuration;
+import org.springframework.context.annotation.PropertySource;
+
+@Configuration
+@PropertySource("classpath:env.properties")
+public class MailConfig {
+}
diff --git a/src/main/java/apptive/devlog/config/WebSecurityConfig.java b/src/main/java/apptive/devlog/config/WebSecurityConfig.java
new file mode 100644
index 0000000..e4d9e67
--- /dev/null
+++ b/src/main/java/apptive/devlog/config/WebSecurityConfig.java
@@ -0,0 +1,67 @@
+package apptive.devlog.config;
+
+import lombok.RequiredArgsConstructor;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.security.authentication.AuthenticationManager;
+import org.springframework.security.config.annotation.authentication.configuration.AuthenticationConfiguration;
+import org.springframework.security.config.annotation.web.builders.HttpSecurity;
+import org.springframework.security.config.annotation.web.configuration.EnableWebSecurity;
+import org.springframework.security.crypto.bcrypt.BCryptPasswordEncoder;
+import org.springframework.security.crypto.password.PasswordEncoder;
+import org.springframework.security.web.SecurityFilterChain;
+
+@Configuration
+@EnableWebSecurity
+@RequiredArgsConstructor
+public class WebSecurityConfig {
+
+    private final CustomUserDetailsService customUserDetailsService;
+
+    @Bean
+    public SecurityFilterChain filterChain(HttpSecurity http) throws Exception {
+        http
+                // CSRF 보호 비활성화(테스트용)
+                .csrf(csrf -> csrf.disable())
+                .headers(headers -> headers
+                        .frameOptions(frameOptions -> frameOptions.sameOrigin()) // H2 콘솔용 설정
+                )
+
+                // URL 별 접근 권한
+                .authorizeHttpRequests((auth) -> auth
+                        // 로그인/회원가입 페이지 인증 없이 접근 허용
+                        .requestMatchers("/users/login", "/users/signup").permitAll()
+                        .requestMatchers("/api/board").permitAll() // board api 테스트용
+                        .requestMatchers("/mail/html").permitAll() // mail api 테스트용
+                        .requestMatchers("/h2-console/**").permitAll() // H2 콘솔용 설정
+                        .anyRequest().authenticated()
+                )
+                .formLogin((form) -> form
+                        .loginPage("/users/login")
+                        // 로그인 성공 시 이동 url
+                        .defaultSuccessUrl("/users/home", true)
+                        // 로그인 페이지 인증 없이 접근 허용
+                        .permitAll()
+                )
+                .logout((logout) -> logout
+                        // 로그아웃 성공 이동 url
+                        .logoutSuccessUrl("/users/login?logout")
+                        // 로그아웃 인증 없이 접근 허용
+                        .permitAll()
+                );
+
+        return http.build();
+    }
+
+    // 인증 관리자 설정 (AuthenticationManager 빈 등록)
+    @Bean
+    public AuthenticationManager authenticationManager(AuthenticationConfiguration config) throws Exception {
+        return config.getAuthenticationManager();
+    }
+
+    // 비밀번호 인코딩(BCrypt)
+    @Bean
+    public PasswordEncoder passwordEncoder() {
+        return new BCryptPasswordEncoder();
+    }
+}
diff --git a/src/main/java/apptive/devlog/mail/controller/MailController.java b/src/main/java/apptive/devlog/mail/controller/MailController.java
new file mode 100644
index 0000000..b2f363a
--- /dev/null
+++ b/src/main/java/apptive/devlog/mail/controller/MailController.java
@@ -0,0 +1,24 @@
+package apptive.devlog.mail.controller;
+
+import apptive.devlog.mail.service.MailService;
+import lombok.RequiredArgsConstructor;
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RestController;
+
+@RestController
+@RequestMapping("/mail")
+@RequiredArgsConstructor
+public class MailController {
+    private final MailService mailService;
+
+    @GetMapping("/simple")
+    public void sendSimpleMailMessage(String email) {
+        mailService.sendSimpleMailMessage(email);
+    }
+
+    @GetMapping("/html")
+    public void sendMimeMessage(String email) {
+        mailService.sendMimeMessage(email);
+    }
+}
diff --git a/src/main/java/apptive/devlog/mail/service/MailService.java b/src/main/java/apptive/devlog/mail/service/MailService.java
new file mode 100644
index 0000000..ef4e475
--- /dev/null
+++ b/src/main/java/apptive/devlog/mail/service/MailService.java
@@ -0,0 +1,75 @@
+package apptive.devlog.mail.service;
+
+import jakarta.mail.internet.MimeMessage;
+import lombok.RequiredArgsConstructor;
+import lombok.extern.slf4j.Slf4j;
+import org.springframework.mail.SimpleMailMessage;
+import org.springframework.mail.javamail.JavaMailSender;
+import org.springframework.mail.javamail.MimeMessageHelper;
+import org.springframework.stereotype.Service;
+import org.springframework.transaction.annotation.Transactional;
+
+@Service
+@Transactional
+@Slf4j
+@RequiredArgsConstructor
+public class MailService {
+
+    private final JavaMailSender javaMailSender;
+
+    public void sendSimpleMailMessage(String email) {
+        SimpleMailMessage simpleMailMessage = new SimpleMailMessage();
+
+        try{
+            simpleMailMessage.setTo(email);
+            simpleMailMessage.setSubject("메일 제목 : 작성 완료");
+            simpleMailMessage.setText("내용 : 글 작성 완료");
+
+            javaMailSender.send(simpleMailMessage);
+
+            log.info("메일 발송 성공!");
+        }
+        catch (Exception e){
+            log.info("메일 발송 실패!");
+            throw new RuntimeException(e);
+        }
+    }
+
+    public void sendMimeMessage(String email) {
+        MimeMessage mimeMessage = javaMailSender.createMimeMessage();
+
+        try{
+            MimeMessageHelper mimeMessageHelper = new MimeMessageHelper(mimeMessage, false, "UTF-8");
+
+            //수신자
+            mimeMessageHelper.setTo(email);
+
+            mimeMessageHelper.setSubject("댓글 알림 메시지입니다.");
+
+            String content = """
+                    <!DOCTYPE html>
+                        <html xmlns:th="http://www.thymeleaf.org">
+                            <body>
+                                <div style="margin:100px;">
+                                    <h1> 댓글 알림 </h1>
+                                    <br>
+                                        <div align="center" style="border:1px solid black;">
+                                            <h3> 작성하신 글에 댓글 또는 대댓글이 추가되었습니다. </h3>
+                                        </div>
+                                    <br/>
+                                </div>
+                            </body>
+                        </html>
+                    """;
+            mimeMessageHelper.setText(content, true);
+
+            javaMailSender.send(mimeMessage);
+
+            log.info("메일 발송 성공!");
+        }
+        catch (Exception e){
+            log.info("메일 발송 실패!");
+            throw new RuntimeException(e);
+        }
+    }
+}
diff --git a/src/main/resources/application.properties b/src/main/resources/application.properties
index 2a9adaf..0f8fd4e 100644
--- a/src/main/resources/application.properties
+++ b/src/main/resources/application.properties
@@ -1,3 +1,23 @@
 spring.application.name=devlog
-spring.datasource.url=none
-spring.autoconfigure.exclude=org.springframework.boot.autoconfigure.jdbc.DataSourceAutoConfiguration
+
+spring.datasource.url=jdbc:h2:mem:testdb
+spring.datasource.driver-class-name=org.h2.Driver
+spring.datasource.username=sa
+spring.datasource.password=
+spring.h2.console.enabled=true
+
+spring.jpa.hibernate.ddl-auto=update
+spring.jpa.show-sql=true
+spring.jpa.properties.hibernate.format_sql=true
+
+# java mail sender
+spring.mail.host=smtp.gmail.com
+spring.mail.port=587
+spring.mail.username=${mail.username}
+spring.mail.password=${mail.password}
+# ?? ? ?? ??
+spring.mail.properties.mail.smtp.auth=true
+spring.mail.properties.mail.smtp.timeout=5000
+# SMTP ?? ?? ?? ??
+spring.mail.properties.mail.smtp.starttls.enable=true
+spring.mail.properties.mail.smtp.starttls.required=true
diff --git a/src/main/resources/env.properties b/src/main/resources/env.properties
new file mode 100644
index 0000000..5f7d948
--- /dev/null
+++ b/src/main/resources/env.properties
@@ -0,0 +1,3 @@
+mail.username=sk124590@gmail.com
+mail.password=atdemcsjqkcnzewc
+#maxevrjivrhgqgcc
\ No newline at end of file
diff --git a/src/main/resources/templates/users/login.html b/src/main/resources/templates/users/login.html
index 0e48773..5cfc909 100644
--- a/src/main/resources/templates/users/login.html
+++ b/src/main/resources/templates/users/login.html
@@ -14,9 +14,9 @@
 <body>
 
 <div class="container">
-    <dic class="py-5 text-center">
+    <div class="py-5 text-center">
         <h2>로그인</h2>
-    </dic>
+    </div>
 
     <form action="/users/login" th:object="${user}" method="post">
         <!-- 이메일 -->
@@ -35,7 +35,7 @@ <h2>로그인</h2>
 
         <div class="row">
             <div class="col">
-                <button class="w-100 btn btn-primary btn-lg" type="submit">회원가입</button>
+                <button class="w-100 btn btn-primary btn-lg" type="submit">로그인</button>
             </div>
             <div class="col">
                 <button class="w-100 btn btn-secondary btn-lg"
diff --git a/src/main/resources/templates/users/signup.html b/src/main/resources/templates/users/signup.html
index e9ba46f..2071b6e 100644
--- a/src/main/resources/templates/users/signup.html
+++ b/src/main/resources/templates/users/signup.html
@@ -29,7 +29,7 @@ <h2>회원가입</h2>
             <input type="email" id="email" th:field="*{email}"
                    th:errorclass="field-error"
                    class="form-control" placeholder="이메일 입력">
-            <div class="field-error" th:erros="*{email}">
+            <div class="field-error" th:errors="*{email}">
                 이메일 오류
             </div>
         </div>
@@ -40,7 +40,7 @@ <h2>회원가입</h2>
             <input type="password" id="password" th:field="*{password}"
                    th:errorclass="field-error"
                    class="form-control" placeholder="비밀번호 입력">
-            <div class="field-error" th:erros="*{password}">
+            <div class="field-error" th:errors="*{password}">
                 비밀번호 오류
             </div>
         </div>
@@ -48,10 +48,10 @@ <h2>회원가입</h2>
         <!-- 이름 -->
         <div>
             <label for="name">이름</label>
-            <input type="text" id="name" th:field="${name}"
+            <input type="text" id="name" th:field="*{name}"
                    th:errorclass="field-error"
                    class="form-control" placeholder="이름 입력">
-            <div class="field-error" th:erros="*{name}">
+            <div class="field-error" th:errors="*{name}">
                 이름 오류
             </div>
         </div>
@@ -59,10 +59,10 @@ <h2>회원가입</h2>
         <!-- 닉네임 -->
         <div>
             <label for="nickname">닉네임</label>
-            <input type="text" id="nickname" th:field="${nickname}"
+            <input type="text" id="nickname" th:field="*{nickname}"
                    th:errorclass="field-error"
                    class="form-control" placeholder="닉네임 입력">
-            <div class="field-error" th:erros="*{nickname}">
+            <div class="field-error" th:errors="*{nickname}">
                 닉네임 오류
             </div>
         </div>
@@ -70,10 +70,10 @@ <h2>회원가입</h2>
         <!-- 생년월일 -->
         <div>
             <label for="birth">생년월일</label>
-            <input type="date" id="birth" th:field="${birth}"
+            <input type="date" id="birth" th:field="*{birth}"
                    th:errorclass="field-error"
                    class="form-control">
-            <div class="field-error" th:erros="*{birth}">
+            <div class="field-error" th:errors="*{birth}">
                 생년월일 오류
             </div>
         </div>
@@ -83,14 +83,14 @@ <h2>회원가입</h2>
             <label>성별</label><br>
             <input type="radio" id="male" name="gender"
                    th:errorclass="field-error"
-                   th:field="*{gender}" value="male">
+                   th:field="*{gender}" value="MALE">
             <label for="male">남</label>
 
             <input type="radio" id="female" name="gender"
                    th:errorclass="field-error"
-                   th:field="*{gender}" value="female">
+                   th:field="*{gender}" value="FEMALE">
             <label for="female">여</label>
-            <div class="field-error" th:erros="*{gender}">
+            <div class="field-error" th:errors="*{gender}">
                 성별 오류
             </div>
         </div>
diff --git a/src/main/resources/templates/users/userHome.html b/src/main/resources/templates/users/userHome.html
index acbca09..30b94d3 100644
--- a/src/main/resources/templates/users/userHome.html
+++ b/src/main/resources/templates/users/userHome.html
@@ -8,7 +8,7 @@
 
 <h1>home</h1>
 
-<h4 th:text="|로그인: ${userLoginForm.email}|">로그인 이메일</h4>
+<h4 th:text="|로그인: ${user.username}|">로그인 이메일</h4>
 
 <a href="/users/login">login</a>
 <a href="/users/signup">signup</a>