diff --git a/src/main/java/Capstone/AutoScheduler/global/repository/EventRepository.java b/src/main/java/Capstone/AutoScheduler/global/repository/EventRepository.java
index 9b5a36e..f4e4cba 100644
--- a/src/main/java/Capstone/AutoScheduler/global/repository/EventRepository.java
+++ b/src/main/java/Capstone/AutoScheduler/global/repository/EventRepository.java
@@ -3,8 +3,11 @@
 import Capstone.AutoScheduler.global.domain.entity.Event;
 import Capstone.AutoScheduler.global.domain.entity.Member;
 import org.springframework.data.jpa.repository.JpaRepository;
+import org.springframework.data.jpa.repository.Query;
+import org.springframework.data.repository.query.Param;
 import org.springframework.stereotype.Repository;
 
+import java.time.LocalDateTime;
 import java.util.List;
 
 @Repository
@@ -12,4 +15,10 @@ public interface EventRepository extends JpaRepository<Event, Long> {
 
     List<Event> findAllByMember(Member member);
     List<Event> findTop10ByMember_MemberIdOrderByCreatedAtDesc(Long memberId);
+
+    @Query("SELECT e FROM Event e WHERE e.member.id = :memberId " +
+            "AND ((:startDate <= e.endDate AND :endDate >= e.startDate))")
+    List<Event> findOverlappingEvents(@Param("memberId") Long memberId,
+                                      @Param("startDate") LocalDateTime startDate,
+                                      @Param("endDate") LocalDateTime endDate);
 }
diff --git a/src/main/java/Capstone/AutoScheduler/global/service/EventService/EventCommandServiceImpl.java b/src/main/java/Capstone/AutoScheduler/global/service/EventService/EventCommandServiceImpl.java
index 81c67c7..5b36018 100644
--- a/src/main/java/Capstone/AutoScheduler/global/service/EventService/EventCommandServiceImpl.java
+++ b/src/main/java/Capstone/AutoScheduler/global/service/EventService/EventCommandServiceImpl.java
@@ -13,6 +13,8 @@
 import org.springframework.stereotype.Service;
 import org.springframework.transaction.annotation.Transactional;
 
+import java.util.List;
+
 @Service
 @RequiredArgsConstructor
 @Transactional
@@ -27,6 +29,12 @@ public class EventCommandServiceImpl implements EventCommandService {
     public Event createEvent(Long memberId, EventRequestDTO.CreateEventRequestDTO request) {
         Member member = findMemberById(memberId);
 
+        // 겹치는 일정 확인
+        List<Event> overlappingEvents = eventRepository.findOverlappingEvents(memberId, request.getStartDate(), request.getEndDate());
+        if (!overlappingEvents.isEmpty()) {
+            throw new IllegalArgumentException("이미 해당 시간에 다른 일정이 존재합니다.");
+        }
+
         Event newEvent = EventConverter.toEvent(request);
         newEvent.setMember(member);