diff --git a/src/main/kotlin/dsm/pick2024/domain/application/service/ApplicationService.kt b/src/main/kotlin/dsm/pick2024/domain/application/service/ApplicationService.kt
index d58d7aa0..4e86323f 100644
--- a/src/main/kotlin/dsm/pick2024/domain/application/service/ApplicationService.kt
+++ b/src/main/kotlin/dsm/pick2024/domain/application/service/ApplicationService.kt
@@ -9,6 +9,7 @@ import dsm.pick2024.domain.application.port.`in`.ApplicationUseCase
 import dsm.pick2024.domain.application.port.out.ExistsApplicationPort
 import dsm.pick2024.domain.application.port.out.SaveApplicationPort
 import dsm.pick2024.domain.application.presentation.dto.request.ApplicationRequest
+import dsm.pick2024.domain.attendance.domain.service.AttendanceService
 import dsm.pick2024.domain.fcm.dto.request.FcmRequest
 import dsm.pick2024.domain.main.port.`in`.MainUseCase
 import dsm.pick2024.domain.outbox.domain.Outbox
@@ -27,7 +28,8 @@ class ApplicationService(
     private val userFacadeUseCase: UserFacadeUseCase,
     private val adminFinderUseCase: AdminFinderUseCase,
     private val saveOutboxPort: SaveOutboxPort,
-    private val mainUseCase: MainUseCase
+    private val mainUseCase: MainUseCase,
+    private val attendanceService: AttendanceService
 ) : ApplicationUseCase {
 
     @Transactional
@@ -37,6 +39,12 @@ class ApplicationService(
             throw AlreadyApplyingForPicnicException
         }
 
+        attendanceService.checkApplicationTime(
+            applicationType = request.applicationType,
+            start = request.start,
+            end = request.end
+        )
+
         saveApplicationPort.save(
             Application(
                 userName = user.name,
diff --git a/src/main/kotlin/dsm/pick2024/domain/attendance/domain/service/AttendanceService.kt b/src/main/kotlin/dsm/pick2024/domain/attendance/domain/service/AttendanceService.kt
index def988fa..8718e2d8 100644
--- a/src/main/kotlin/dsm/pick2024/domain/attendance/domain/service/AttendanceService.kt
+++ b/src/main/kotlin/dsm/pick2024/domain/attendance/domain/service/AttendanceService.kt
@@ -3,6 +3,7 @@ package dsm.pick2024.domain.attendance.domain.service
 import dsm.pick2024.domain.application.enums.ApplicationType
 import dsm.pick2024.domain.attendance.domain.Attendance
 import dsm.pick2024.domain.attendance.enums.AttendanceStatus
+import dsm.pick2024.domain.attendance.exception.InvalidPeriodException
 import org.springframework.stereotype.Component
 import java.time.LocalTime
 
@@ -14,7 +15,7 @@ class AttendanceService {
             LocalTime.of(8, 40) to LocalTime.of(9, 40), // 1교시
             LocalTime.of(9, 40) to LocalTime.of(10, 40), // 2교시
             LocalTime.of(10, 40) to LocalTime.of(11, 40), // 3교시
-            LocalTime.of(12, 40) to LocalTime.of(13, 30), // 4교시
+            LocalTime.of(11, 40) to LocalTime.of(13, 30), // 4교시
             LocalTime.of(13, 30) to LocalTime.of(14, 40), // 5교시
             LocalTime.of(14, 30) to LocalTime.of(15, 30), // 6교시
             LocalTime.of(15, 30) to LocalTime.of(16, 30), // 7교시
@@ -29,17 +30,70 @@ class AttendanceService {
     }
 
     // 교시 혹은 시간을 기반으로 교시 목록을 반환하는 함수
-    fun translateApplication(start: String, end: String?, applicationType: ApplicationType): List<String> {
+    fun translateApplication(start: String, end: String, applicationType: ApplicationType): Pair<String, String> {
         return when (applicationType) {
-            ApplicationType.PERIOD -> listOf(start, end!!)
+            ApplicationType.PERIOD -> Pair(start, end)
             ApplicationType.TIME -> {
                 val startTime = LocalTime.parse(start)
-                val endTime = end?.let { LocalTime.parse(it) }
+                val endTime = LocalTime.parse(end)
                 getMatchPeriods(startTime, endTime)
             }
         }
     }
 
+    fun checkApplicationTime(applicationType: ApplicationType, start: String, end: String) {
+        when (applicationType) {
+            ApplicationType.TIME -> {
+                val startTime = LocalTime.parse(start)
+                val endTime = LocalTime.parse(end)
+                if (startTime > endTime ||
+                    endTime > LocalTime.of(20, 30) ||
+                    startTime < LocalTime.of(8, 30)
+                ) {
+                    throw InvalidPeriodException
+                }
+            }
+            ApplicationType.PERIOD -> {
+                val startPeriod = start.replace("교시", "").toIntOrNull() ?: throw InvalidPeriodException
+                val endPeriod = end.replace("교시", "").toIntOrNull() ?: throw InvalidPeriodException
+                if (startPeriod > endPeriod || startPeriod < 1 || endPeriod > 10) {
+                    throw InvalidPeriodException
+                }
+            }
+        }
+    }
+
+    fun checkEarlyReturnTime(applicationType: ApplicationType, start: String) {
+        when (applicationType) {
+            ApplicationType.TIME -> {
+                val startTime = LocalTime.parse(start)
+                if (startTime < LocalTime.of(8, 30)) {
+                    throw InvalidPeriodException
+                }
+            }
+            ApplicationType.PERIOD -> {
+                val startPeriod = start.replace("교시", "").toInt()
+                if (startPeriod < 1 || startPeriod > 10) {
+                    throw InvalidPeriodException
+                }
+            }
+        }
+    }
+
+    fun translateEarlyReturn(start: String, applicationType: ApplicationType): String {
+        return when (applicationType) {
+            ApplicationType.PERIOD -> start
+            ApplicationType.TIME -> {
+                val startTime = LocalTime.parse(start)
+                val startIndex = periods.indexOfFirst { (start, endAt) ->
+                    startTime >= start && startTime < endAt
+                }
+                if (startIndex == -1) throw InvalidPeriodException
+                periodNames[startIndex]
+            }
+        }
+    }
+
     // 주어진 교시 혹은 시간에 해당하는 출석 상태를 업데이트하는 함수
     fun updateAttendanceToApplication(
         start: String,
@@ -113,27 +167,16 @@ class AttendanceService {
         return updateAttendance
     }
 
-    fun translateEarlyReturn(start: String, applicationType: ApplicationType): List<String> {
-        return when (applicationType) {
-            ApplicationType.PERIOD -> {
-                val startIndex = periodNames.indexOf(start).coerceAtLeast(0)
-                periodNames.subList(startIndex, periodNames.size)
-            }
-            ApplicationType.TIME -> {
-                val startTime = LocalTime.parse(start)
-                getMatchPeriods(startTime, null)
-            }
+    private fun getMatchPeriods(startTime: LocalTime, endTime: LocalTime): Pair<String, String> {
+        val startIndex = periods.indexOfFirst { (start, endAt) ->
+            startTime in start..endAt
+        }
+        val endIndex = periods.indexOfFirst { (start, endAt) ->
+            endTime in start..endAt
         }
-    }
 
-    private fun getMatchPeriods(startTime: LocalTime, endTime: LocalTime?): List<String> {
-        return periods
-            .mapIndexed { index, period ->
-                if ((startTime < period.second) && (endTime == null || endTime > period.first)) {
-                    periodNames[index]
-                } else {
-                    null
-                }
-            }.filterNotNull()
+        if (startIndex == -1 || endIndex == -1) throw InvalidPeriodException
+
+        return periodNames[startIndex] to periodNames[endIndex]
     }
 }
diff --git a/src/main/kotlin/dsm/pick2024/domain/earlyreturn/service/CreateEarlyReturnService.kt b/src/main/kotlin/dsm/pick2024/domain/earlyreturn/service/CreateEarlyReturnService.kt
index c2e3a718..5898b609 100644
--- a/src/main/kotlin/dsm/pick2024/domain/earlyreturn/service/CreateEarlyReturnService.kt
+++ b/src/main/kotlin/dsm/pick2024/domain/earlyreturn/service/CreateEarlyReturnService.kt
@@ -6,6 +6,7 @@ import dsm.pick2024.domain.application.enums.ApplicationKind
 import dsm.pick2024.domain.application.enums.Status
 import dsm.pick2024.domain.application.port.out.ExistsApplicationPort
 import dsm.pick2024.domain.application.port.out.SaveApplicationPort
+import dsm.pick2024.domain.attendance.domain.service.AttendanceService
 import dsm.pick2024.domain.earlyreturn.exception.AlreadyApplyingForEarlyReturnException
 import dsm.pick2024.domain.earlyreturn.port.`in`.CreateEarlyReturnUseCase
 import dsm.pick2024.domain.earlyreturn.presentation.dto.request.CreateEarlyReturnRequest
@@ -24,7 +25,8 @@ class CreateEarlyReturnService(
     private val userFacadeUseCase: UserFacadeUseCase,
     private val adminFinderUseCase: AdminFinderUseCase,
     private val outboxFacadeUseCase: OutboxFacadeUseCase,
-    private val mainUseCase: MainUseCase
+    private val mainUseCase: MainUseCase,
+    private val attendanceService: AttendanceService
 ) : CreateEarlyReturnUseCase {
     @Transactional
     override fun createEarlyReturn(request: CreateEarlyReturnRequest) {
@@ -34,6 +36,8 @@ class CreateEarlyReturnService(
             throw AlreadyApplyingForEarlyReturnException
         }
 
+        attendanceService.checkEarlyReturnTime(request.applicationType, request.start)
+
         saveApplicationPort.save(
             Application(
                 userName = user.name,
diff --git a/src/main/kotlin/dsm/pick2024/domain/earlyreturn/service/processor/EarlyReturnApprovalProcessor.kt b/src/main/kotlin/dsm/pick2024/domain/earlyreturn/service/processor/EarlyReturnApprovalProcessor.kt
index a53d4ab8..1e5b9a00 100644
--- a/src/main/kotlin/dsm/pick2024/domain/earlyreturn/service/processor/EarlyReturnApprovalProcessor.kt
+++ b/src/main/kotlin/dsm/pick2024/domain/earlyreturn/service/processor/EarlyReturnApprovalProcessor.kt
@@ -53,7 +53,7 @@ class EarlyReturnApprovalProcessor(
         return ApplicationStory(
             reason = application.reason,
             userName = application.userName,
-            start = start.first(),
+            start = start,
             date = application.date,
             type = Type.EARLY_RETURN,
             userId = application.userId