diff --git a/build.gradle b/build.gradle
index 674a9c4..905bfdb 100644
--- a/build.gradle
+++ b/build.gradle
@@ -25,7 +25,6 @@ dependencies {
 	testImplementation 'org.springframework.boot:spring-boot-starter-test'
 	testRuntimeOnly 'org.junit.platform:junit-platform-launcher'
 	implementation 'org.springdoc:springdoc-openapi-ui:1.6.12'
-	runtimeOnly 'com.h2database:h2'
 }
 
 tasks.named('test') {
diff --git a/src/main/java/com/hyunsolution/dangu/participant/Participant.java b/src/main/java/com/hyunsolution/dangu/participant/domain/Participant.java
similarity index 96%
rename from src/main/java/com/hyunsolution/dangu/participant/Participant.java
rename to src/main/java/com/hyunsolution/dangu/participant/domain/Participant.java
index 46dae07..b21e3b5 100644
--- a/src/main/java/com/hyunsolution/dangu/participant/Participant.java
+++ b/src/main/java/com/hyunsolution/dangu/participant/domain/Participant.java
@@ -1,4 +1,4 @@
-package com.hyunsolution.dangu.participant;
+package com.hyunsolution.dangu.participant.domain;
 
 import com.hyunsolution.dangu.user.domain.User;
 import com.hyunsolution.dangu.workspace.domain.Workspace;
diff --git a/src/main/java/com/hyunsolution/dangu/participant/domain/ParticipantRepository.java b/src/main/java/com/hyunsolution/dangu/participant/domain/ParticipantRepository.java
index 1266dc7..764775a 100644
--- a/src/main/java/com/hyunsolution/dangu/participant/domain/ParticipantRepository.java
+++ b/src/main/java/com/hyunsolution/dangu/participant/domain/ParticipantRepository.java
@@ -1,24 +1,19 @@
 package com.hyunsolution.dangu.participant.domain;
 
-import com.hyunsolution.dangu.participant.Participant;
-import com.hyunsolution.dangu.user.domain.User;
 import java.util.List;
 import java.util.Optional;
 import org.springframework.data.jpa.repository.JpaRepository;
 import org.springframework.data.jpa.repository.Query;
 import org.springframework.data.repository.query.Param;
 
-public interface ParticipantRepository extends JpaRepository<User, Long> {
+public interface ParticipantRepository extends JpaRepository<Participant, Long> {
 
     // 같은 방에 있는 사람들 id(PK) 리스트
     @Query(value = "SELECT p.id FROM Participant p WHERE p.workspace.id=:workspaceId")
-    List<Long> findByVisitorMatch(Long workspaceId);
+    List<Long> findParticipantIdByWorkspaceId(Long workspaceId);
 
     // ID별 매칭버튼 클릭 여부
-    @Query(
-            value =
-                    "SELECT COUNT(p) >0 FROM Participant p WHERE p.id=:id AND p.participantMatch=true")
-    Boolean existsById(long id);
+    Boolean existsByIdAndParticipantMatchTrue(long id);
 
     // 개인 ID 찾기
     @Query(
diff --git a/src/main/java/com/hyunsolution/dangu/participant/service/ParticipantService.java b/src/main/java/com/hyunsolution/dangu/participant/service/ParticipantService.java
index ffbf706..597dd02 100644
--- a/src/main/java/com/hyunsolution/dangu/participant/service/ParticipantService.java
+++ b/src/main/java/com/hyunsolution/dangu/participant/service/ParticipantService.java
@@ -1,11 +1,12 @@
 package com.hyunsolution.dangu.participant.service;
 
-import com.hyunsolution.dangu.participant.Participant;
+import com.hyunsolution.dangu.participant.domain.Participant;
 import com.hyunsolution.dangu.participant.domain.ParticipantRepository;
 import com.hyunsolution.dangu.user.domain.UserRepository;
 import com.hyunsolution.dangu.workspace.domain.Workspace;
 import com.hyunsolution.dangu.workspace.domain.WorkspaceRepository;
 import java.util.List;
+import java.util.NoSuchElementException;
 import java.util.Optional;
 import lombok.RequiredArgsConstructor;
 import org.springframework.stereotype.Service;
@@ -21,25 +22,24 @@ public class ParticipantService {
     @Transactional
     public void changeMatching(Long id, Long workspaceId) {
         // 상태 변경
+        Participant participantOptional =
+                participantRepository.findByUserIdAndWorkspaceId(id, workspaceId)
+                        .orElseThrow(()-> new NoSuchElementException("Participant not found"));
 
-        Optional<Participant> participantOptional =
-                participantRepository.findByUserIdAndWorkspaceId(id, workspaceId);
-        participantOptional.get().accept();
-        //        participantRepository.updateByIdAndWorkspace(id, workspaceId);
+        participantOptional.accept();
 
         // participant테이블에서 roomNumber로 들어온 숫자를 통해 누가 있는지 파악
-        List<Long> participants = participantRepository.findByVisitorMatch(workspaceId);
+        List<Long> participantIds = participantRepository.findParticipantIdByWorkspaceId(workspaceId);
 
-        for (Long participant : participants) {
-            boolean mathingCheck = participantRepository.existsById(participant);
+        // 방안에 모든 참가자가 "확정"버튼을 눌렀는지 확인
+        for (Long participant : participantIds) {
+            boolean mathingCheck = participantRepository.existsByIdAndParticipantMatchTrue(participant);
             if (!mathingCheck) {
                 return;
             }
         }
-        // 방안에 모든 참가자가 "확정"버튼을 눌렀는지 확인하고 게임방 테이블 속 매칭 결과를 true로 바꿈
-        Workspace workspace1 = workspaceRepository.findById(workspaceId).get();
-        workspace1.finalAccept();
-        //        workspaceRepository.UpdateWorkspaceStatus(workspaceId);
-
+        // 게임방 테이블 속 매칭 결과를 true로 바꿈
+        Workspace workspace1 = workspaceRepository.findById(workspaceId).orElseThrow(()-> new NoSuchElementException("Workspace not found"));
+        workspace1.acceptFinal();
     }
 }
diff --git a/src/main/java/com/hyunsolution/dangu/user/domain/UserRepository.java b/src/main/java/com/hyunsolution/dangu/user/domain/UserRepository.java
index d4383dd..e1d05ec 100644
--- a/src/main/java/com/hyunsolution/dangu/user/domain/UserRepository.java
+++ b/src/main/java/com/hyunsolution/dangu/user/domain/UserRepository.java
@@ -1,8 +1,9 @@
 package com.hyunsolution.dangu.user.domain;
 
-import java.util.Optional;
 import org.springframework.data.jpa.repository.JpaRepository;
 
+import java.util.Optional;
+
 public interface UserRepository extends JpaRepository<User, Long> {
     Optional<User> findByUid(String uid);
 }
diff --git a/src/main/java/com/hyunsolution/dangu/workspace/domain/WorkspaceRepository.java b/src/main/java/com/hyunsolution/dangu/workspace/domain/WorkspaceRepository.java
index 84dbf1e..7c7d524 100644
--- a/src/main/java/com/hyunsolution/dangu/workspace/domain/WorkspaceRepository.java
+++ b/src/main/java/com/hyunsolution/dangu/workspace/domain/WorkspaceRepository.java
@@ -1,10 +1,12 @@
 package com.hyunsolution.dangu.workspace.domain;
 
 import org.springframework.data.jpa.repository.JpaRepository;
+import org.springframework.data.jpa.repository.Modifying;
 import org.springframework.data.jpa.repository.Query;
 
 public interface WorkspaceRepository extends JpaRepository<Workspace, Long> {
 
+    @Modifying
     @Query(value = "UPDATE Workspace w SET w.isMatched=true WHERE w.id=:workspaceId")
     void UpdateWorkspaceStatus(Long workspaceId);
 }