diff --git a/src/main/java/com/waruru/areyouhere/attendee/controller/AttendeeController.java b/src/main/java/com/waruru/areyouhere/attendee/controller/AttendeeController.java
index 6853499..28a44a2 100644
--- a/src/main/java/com/waruru/areyouhere/attendee/controller/AttendeeController.java
+++ b/src/main/java/com/waruru/areyouhere/attendee/controller/AttendeeController.java
@@ -1,5 +1,6 @@
 package com.waruru.areyouhere.attendee.controller;
 
+import com.waruru.areyouhere.attendee.dto.request.UpdateAttendeesRequestDto;
 import com.waruru.areyouhere.attendee.service.dto.AttendeeDetailDto;
 import com.waruru.areyouhere.attendee.dto.response.ClassAttendeesResponseDto;
 import com.waruru.areyouhere.attendee.dto.request.DeleteAttendeesRequestDto;
@@ -16,6 +17,7 @@
 import org.springframework.http.ResponseEntity;
 import org.springframework.web.bind.annotation.GetMapping;
 import org.springframework.web.bind.annotation.PostMapping;
+import org.springframework.web.bind.annotation.PutMapping;
 import org.springframework.web.bind.annotation.RequestBody;
 import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.bind.annotation.RequestParam;
@@ -65,5 +67,12 @@ public ResponseEntity<DuplicateAttendees> checkDuplicate(@RequestBody DuplicateC
     public ResponseEntity<AttendeeDetailDto> getAttendeeDetail(@RequestParam("attendeeId") Long attendeeId){
         return ResponseEntity.ok(attendeeService.getAttendanceCount(attendeeId));
     }
+
+    @LoginRequired
+    @PutMapping
+    public ResponseEntity<HttpStatus> update(@RequestBody UpdateAttendeesRequestDto UpdateAttendeesRequestDto){
+        attendeeService.updateAll(UpdateAttendeesRequestDto.getCourseId(), UpdateAttendeesRequestDto.getUpdatedAttendees());
+        return ResponseEntity.ok().build();
+    }
 }
 
diff --git a/src/main/java/com/waruru/areyouhere/attendee/dto/request/UpdateAttendeesRequestDto.java b/src/main/java/com/waruru/areyouhere/attendee/dto/request/UpdateAttendeesRequestDto.java
index 4458b96..03fe96e 100644
--- a/src/main/java/com/waruru/areyouhere/attendee/dto/request/UpdateAttendeesRequestDto.java
+++ b/src/main/java/com/waruru/areyouhere/attendee/dto/request/UpdateAttendeesRequestDto.java
@@ -2,7 +2,9 @@
 
 import com.waruru.areyouhere.attendee.service.dto.AttendeeInfo;
 import java.util.List;
+import lombok.Getter;
 
+@Getter
 public class UpdateAttendeesRequestDto {
     private Long courseId;
     private List<AttendeeInfo> updatedAttendees;
diff --git a/src/main/java/com/waruru/areyouhere/attendee/service/AttendeeService.java b/src/main/java/com/waruru/areyouhere/attendee/service/AttendeeService.java
index 3dcf51b..2a7767d 100644
--- a/src/main/java/com/waruru/areyouhere/attendee/service/AttendeeService.java
+++ b/src/main/java/com/waruru/areyouhere/attendee/service/AttendeeService.java
@@ -2,6 +2,7 @@
 
 import com.waruru.areyouhere.attendee.service.dto.AttendeeData;
 import com.waruru.areyouhere.attendee.service.dto.AttendeeDetailDto;
+import com.waruru.areyouhere.attendee.service.dto.AttendeeInfo;
 import com.waruru.areyouhere.attendee.service.dto.ClassAttendees;
 import com.waruru.areyouhere.attendee.service.dto.DuplicateAttendees;
 import com.waruru.areyouhere.attendee.service.dto.SessionAttendees;
@@ -24,4 +25,6 @@ public interface AttendeeService {
     public DuplicateAttendees getDuplicatesAll(Long courseId, List<String> newAttendees);
 
     public AttendeeDetailDto getAttendanceCount(Long attendeeId);
+
+    public void updateAll(Long courseId, List<AttendeeInfo> updatedAttendees);
 }
diff --git a/src/main/java/com/waruru/areyouhere/attendee/service/AttendeeServiceImpl.java b/src/main/java/com/waruru/areyouhere/attendee/service/AttendeeServiceImpl.java
index 3d7ccdc..bb48d38 100644
--- a/src/main/java/com/waruru/areyouhere/attendee/service/AttendeeServiceImpl.java
+++ b/src/main/java/com/waruru/areyouhere/attendee/service/AttendeeServiceImpl.java
@@ -194,10 +194,21 @@ public AttendeeDetailDto getAttendanceCount(Long attendeeId){
                 .build();
     }
 
+    @Override
     public void updateAll(Long courseId, List<AttendeeInfo> updatedAttendees){
         List<Attendee> attendees = attendeeRepository.findAttendeesByCourse_Id(courseId);
         Map<Long, Attendee> attendeeMap = attendees.stream().collect(Collectors.toMap(Attendee::getId, attendee -> attendee));
         //TODO: duplicate 처리
+
+        List<String> attendeeUniqueCheck = updatedAttendees.stream()
+                .map(attendeeData ->
+                        attendeeData.getName() + (attendeeData.getNote() == null ? "" : attendeeData.getNote())
+                ).toList();
+
+        if(!isUnique(attendeeUniqueCheck, courseId)){
+            throw new AttendeesNotUniqueException("참여자 이름이 중복되었습니다.");
+        }
+
         updatedAttendees.stream()
                 .map(attendee ->
                     attendeeMap.get(attendee.getId())