diff --git a/src/main/java/com/hanaro/triptogether/teamMember/domain/TeamMemberRepository.java b/src/main/java/com/hanaro/triptogether/teamMember/domain/TeamMemberRepository.java
index 51f7a71..6a03097 100644
--- a/src/main/java/com/hanaro/triptogether/teamMember/domain/TeamMemberRepository.java
+++ b/src/main/java/com/hanaro/triptogether/teamMember/domain/TeamMemberRepository.java
@@ -1,5 +1,6 @@
 package com.hanaro.triptogether.teamMember.domain;
 
+import com.hanaro.triptogether.member.domain.Member;
 import com.hanaro.triptogether.team.domain.Team;
 import org.springframework.data.jpa.repository.JpaRepository;
 import org.springframework.data.jpa.repository.Query;
@@ -18,4 +19,6 @@ public interface TeamMemberRepository extends JpaRepository<TeamMember,Long> {
     List<TeamMember> findTeamMemberByMember_MemberIdx(Long memberIdx);
 
     Optional<TeamMember> findTeamMemberByMember_MemberIdxAndTeam_TeamIdx(Long memberIdx, Long teamIdx);
+
+    TeamMember findTeamMemberByMemberAndTeam(Member member, Team team);
 }
diff --git a/src/main/java/com/hanaro/triptogether/teamMember/service/impl/TeamMemberServiceImpl.java b/src/main/java/com/hanaro/triptogether/teamMember/service/impl/TeamMemberServiceImpl.java
index 52daa22..e2907de 100644
--- a/src/main/java/com/hanaro/triptogether/teamMember/service/impl/TeamMemberServiceImpl.java
+++ b/src/main/java/com/hanaro/triptogether/teamMember/service/impl/TeamMemberServiceImpl.java
@@ -193,13 +193,20 @@ public void joinTeamMember(JoinTeamMemberReq joinTeamMemberReq) {
         Member member = memberRepository.findById(joinTeamMemberReq.getMemberIdx()).orElseThrow(() -> new ApiException(ExceptionEnum.MEMBER_NOT_FOUND));
         Team team = teamRepository.findById(joinTeamMemberReq.getTeamIdx()).orElseThrow(() -> new ApiException(ExceptionEnum.TEAM_NOT_FOUND));
 
-        TeamMember teamMember = TeamMember.builder()
-                .team(team)
-                .member(member)
-                .teamMemberState(TeamMemberState.수락대기)
-                .createdAt(LocalDateTime.now()).build();
-
-        teamMemberRepository.save(teamMember);
+        TeamMember existingTeamMember = teamMemberRepository.findTeamMemberByMemberAndTeam(member, team);
+
+        if (existingTeamMember != null) {
+            existingTeamMember.updateTeamMemberState(TeamMemberState.수락대기);
+            teamMemberRepository.save(existingTeamMember);
+        } else {
+            TeamMember teamMember = TeamMember.builder()
+                    .team(team)
+                    .member(member)
+                    .teamMemberState(TeamMemberState.수락대기)
+                    .createdAt(LocalDateTime.now())
+                    .build();
+            teamMemberRepository.save(teamMember);
+        }
     }
 
     @Override