diff --git a/src/pages/admin/ClubDetailEdit/Page.tsx b/src/pages/admin/ClubDetailEdit/Page.tsx
index 6d06a5c5..923cfbab 100644
--- a/src/pages/admin/ClubDetailEdit/Page.tsx
+++ b/src/pages/admin/ClubDetailEdit/Page.tsx
@@ -48,11 +48,8 @@ export const ClubDetailEditPage = () => {
             color: 'white',
           },
           duration: 1000,
+          onAutoClose: () => navigate(`/clubs/${clubId}`),
         });
-
-        setTimeout(() => {
-          navigate(`/clubs/${clubId}`);
-        }, 1000);
       })
       .catch(() => {
         toast.error('수정 실패!', {
diff --git a/src/pages/admin/Login/KakaoCallback.tsx b/src/pages/admin/Login/KakaoCallback.tsx
index 052ad084..57afabac 100644
--- a/src/pages/admin/Login/KakaoCallback.tsx
+++ b/src/pages/admin/Login/KakaoCallback.tsx
@@ -1,41 +1,54 @@
-import axios from 'axios';
 import { useEffect } from 'react';
 import { useNavigate } from 'react-router-dom';
 import { LoadingSpinner } from '@/shared/components/LoadingSpinner';
+import { postAuthCode } from './api/postAuthCode';
+import { setAccessToken, setTemporaryToken } from '../Signup/utils/token';
+import type { ErrorResponse } from '../Signup/type/error';
+import type { AxiosError } from 'axios';
+
+interface LoginSuccessResponse {
+  status: 'LOGIN_SUCCESS';
+  accessToken: string;
+  refreshToken: string;
+}
+
+interface RegistrationRequiredResponse {
+  status: 'REGISTRATION_REQUIRED';
+  temporaryToken: string;
+}
+
+type LoginResponse = LoginSuccessResponse | RegistrationRequiredResponse;
 
 export const KakaoCallback = () => {
   const navigate = useNavigate();
 
   useEffect(() => {
     const code = new URL(window.location.href).searchParams.get('code');
-    if (!code) return;
 
-    console.log(code);
+    if (!code) {
+      navigate('/login');
+      return;
+    }
+
     const fetchToken = async () => {
       try {
-        const res = axios.post(`${import.meta.env.VITE_API_BASE_URL}/auth/kakao/login`, {
-          authorizationCode: code,
-        });
-        console.log('응답res ', res);
-
-        // CASE 1) 기존 회원
-
-        // 1-1. accessToken, refreshToken 발급
-        // localStorage.setItem('accessToken', res.data.accessToken);
-        // localStorage.setItem('refreshToken ', res.data.refreshToken)- (수정전)
-        // refreshToken은 httpOnly 관리(수정후)
-        // ------------------------------------------------------------
-        // 2-2 main 페이지 이동
-        // navigate('/'); // 로그인 후 홈으로 이동
-
-        // CASE 2) 기존 회원
-        // 2-1. 임시 토큰
-        // 2-2. navigate('/signup')
-      } catch (error) {
-        console.log('error:', error);
+        const response: LoginResponse = await postAuthCode(code);
+
+        switch (response.status) {
+          case 'LOGIN_SUCCESS':
+            setAccessToken(response.accessToken);
+            navigate('/');
+            break;
+          case 'REGISTRATION_REQUIRED':
+            setTemporaryToken(response.temporaryToken);
+            navigate('/signup');
+            break;
+        }
+      } catch (e) {
+        const error = e as AxiosError<ErrorResponse>;
+        return new Error(error.response?.data.message);
       }
     };
-
     fetchToken();
   }, [navigate]);
 
diff --git a/src/pages/admin/Login/api/initInstance.ts b/src/pages/admin/Login/api/initInstance.ts
new file mode 100644
index 00000000..f379341a
--- /dev/null
+++ b/src/pages/admin/Login/api/initInstance.ts
@@ -0,0 +1,20 @@
+import axios from 'axios';
+import type { AxiosInstance, CreateAxiosDefaults } from 'axios';
+
+const initInstance = (config: CreateAxiosDefaults): AxiosInstance => {
+  const instance = axios.create({
+    timeout: 10000,
+    headers: {
+      'Content-Type': 'application/json',
+      ...config.headers,
+    },
+    // TODO 0. interceptor 적용지점(동아리 운영자)
+    ...config,
+  });
+
+  return instance;
+};
+
+export const apiInstance = initInstance({
+  baseURL: import.meta.env.VITE_API_BASE_URL,
+});
diff --git a/src/pages/admin/Login/api/postAuthCode.ts b/src/pages/admin/Login/api/postAuthCode.ts
new file mode 100644
index 00000000..934a0169
--- /dev/null
+++ b/src/pages/admin/Login/api/postAuthCode.ts
@@ -0,0 +1,22 @@
+import { apiInstance } from './initInstance';
+import type { AxiosResponse } from 'axios';
+
+interface LoginSuccessResponse {
+  status: 'LOGIN_SUCCESS';
+  accessToken: string;
+  refreshToken: string;
+}
+
+interface RegistrationRequiredResponse {
+  status: 'REGISTRATION_REQUIRED';
+  temporaryToken: string;
+}
+
+type LoginResponse = LoginSuccessResponse | RegistrationRequiredResponse;
+
+export const postAuthCode = async (code: string): Promise<LoginResponse> => {
+  const response: AxiosResponse<LoginResponse> = await apiInstance.post('/auth/kakao/login', {
+    authorizationCode: code,
+  });
+  return response.data;
+};
diff --git a/src/pages/admin/Signup/api/signup.ts b/src/pages/admin/Signup/api/signup.ts
index 67431b40..0f1bf589 100644
--- a/src/pages/admin/Signup/api/signup.ts
+++ b/src/pages/admin/Signup/api/signup.ts
@@ -1,15 +1,43 @@
+import axios, { AxiosError, type AxiosResponse } from 'axios';
+import { apiInstance } from '../../Login/api/initInstance';
+import type { ErrorResponse } from '../type/error';
 import type { SignupFormInputs } from '../type/signup';
 
-export const postSignupForm = async (formData: SignupFormInputs): Promise<SignupFormInputs> => {
-  const url = `${import.meta.env.VITE_API_BASE_URL}/auth/register`;
-  const response = await fetch(url, {
-    method: 'POST',
-    headers: {
-      'Content-Type': 'application/json',
-    },
-    body: JSON.stringify(formData),
-  });
+export interface RegisterSuccessResponse {
+  status: 'REGISTER_SUCCESS';
+  accessToken: string;
+  refreshToken: string;
+}
 
-  if (!response.ok) throw new Error('회원 가입 양식을 제출하지 못했습니다.');
-  return await response.json();
+export const postSignupForm = async (
+  formData: SignupFormInputs,
+  tempToken: string,
+): Promise<RegisterSuccessResponse> => {
+  try {
+    const response: AxiosResponse<RegisterSuccessResponse> = await apiInstance.post(
+      '/auth/register',
+      formData,
+      {
+        headers: { Authorization: `Bearer ${tempToken}` },
+      },
+    );
+    return response.data;
+  } catch (e: unknown) {
+    if (axios.isAxiosError(e)) {
+      const error = e as AxiosError<ErrorResponse>;
+      const status = error.response?.status;
+      const detailMsg = error.response?.data.detail;
+      switch (status) {
+        case 400:
+          throw new Error(`입력 오류: ${detailMsg}`);
+        case 401:
+          throw new Error(`권한 오류: ${detailMsg}`);
+        case 409:
+          throw new Error(`중복 오류: ${detailMsg}`);
+        default:
+          throw new Error(`알 수 없는 오류: ${e.message}`);
+      }
+    }
+    throw e;
+  }
 };
diff --git a/src/pages/admin/Signup/components/SignupForm/index.tsx b/src/pages/admin/Signup/components/SignupForm/index.tsx
index 28fc77ab..d4d04459 100644
--- a/src/pages/admin/Signup/components/SignupForm/index.tsx
+++ b/src/pages/admin/Signup/components/SignupForm/index.tsx
@@ -1,11 +1,12 @@
 import { useForm, FormProvider } from 'react-hook-form';
 import { useNavigate } from 'react-router-dom';
 import { toast } from 'sonner';
-import { postSignupForm } from '@/pages/admin/Signup/api/signup';
+import { postSignupForm, type RegisterSuccessResponse } from '@/pages/admin/Signup/api/signup';
 import * as S from '@/pages/admin/Signup/components/SignupForm/index.styled';
 import { Button } from '@/shared/components/Button';
 import { OutlineInputField } from '@/shared/components/Form/InputField/OutlineInputField';
 import { theme } from '@/styles/theme';
+import { getTemporaryToken, setAccessToken } from '../../utils/token';
 import type { SignupFormInputs } from '@/pages/admin/Signup/type/signup';
 
 export const SignupForm = () => {
@@ -20,28 +21,38 @@ export const SignupForm = () => {
       phoneNumber: '',
     },
   });
-
   const { errors, isSubmitting } = methods.formState;
 
   const onSubmit = async (signupFormValue: SignupFormInputs) => {
+    const temporaryToken = getTemporaryToken();
+
+    if (!temporaryToken) {
+      toast.error('회원가입을 위한 토큰이 존재하지 않습니다.');
+      return;
+    }
+
     try {
-      await postSignupForm(signupFormValue);
+      const response: RegisterSuccessResponse = await postSignupForm(
+        signupFormValue,
+        temporaryToken,
+      );
+
+      setAccessToken(response.accessToken);
       toast.success('회원가입 완료!', {
         style: { backgroundColor: theme.colors.primary, color: 'white' },
         duration: 1000,
+        onAutoClose: () => navigate('/'),
       });
-      setTimeout(() => {
-        navigate(`/login`);
-      }, 1000);
-    } catch (e) {
-      console.error(e);
-      toast.error('회원가입 실패!', {
-        duration: 1000,
-        style: {
-          backgroundColor: 'white',
-          color: theme.colors.error,
-        },
-      });
+    } catch (e: unknown) {
+      if (e instanceof Error) {
+        toast.error(e.message, {
+          duration: 1000,
+          style: {
+            backgroundColor: 'white',
+            color: theme.colors.error,
+          },
+        });
+      }
     }
   };
 
diff --git a/src/pages/admin/Signup/type/error.ts b/src/pages/admin/Signup/type/error.ts
new file mode 100644
index 00000000..5bf09f8f
--- /dev/null
+++ b/src/pages/admin/Signup/type/error.ts
@@ -0,0 +1,5 @@
+export interface ErrorResponse {
+  status: number;
+  message: string;
+  detail: string;
+}
diff --git a/src/pages/admin/Signup/utils/token.ts b/src/pages/admin/Signup/utils/token.ts
new file mode 100644
index 00000000..032a0f94
--- /dev/null
+++ b/src/pages/admin/Signup/utils/token.ts
@@ -0,0 +1,5 @@
+export const setAccessToken = (token: string) => localStorage.setItem('accessToken', token);
+export const getAccessToken = () => localStorage.getItem('accessToken');
+export const getRefreshToken = () => localStorage.getItem('refreshToken');
+export const setTemporaryToken = (token: string) => sessionStorage.setItem('temporaryToken', token);
+export const getTemporaryToken = () => sessionStorage.getItem('temporaryToken');
diff --git a/src/pages/user/Apply/components/ApplicationForm/index.tsx b/src/pages/user/Apply/components/ApplicationForm/index.tsx
index 3e8b308d..9cec999b 100644
--- a/src/pages/user/Apply/components/ApplicationForm/index.tsx
+++ b/src/pages/user/Apply/components/ApplicationForm/index.tsx
@@ -45,10 +45,8 @@ export const ApplicationForm = ({ questions }: Props) => {
             color: 'white',
           },
           duration: 1000,
+          onAutoClose: () => navigate(`/clubs/${clubIdNumber}`),
         });
-        setTimeout(() => {
-          navigate(`/clubs/${clubIdNumber}`);
-        }, 1000);
       })
       .catch(() => {
         toast.error('제출 실패!', {