diff --git a/backend/src/main/java/org/sejongisc/backend/attendance/entity/Attendance.java b/backend/src/main/java/org/sejongisc/backend/attendance/entity/Attendance.java
index d87c9bb0..5219b874 100644
--- a/backend/src/main/java/org/sejongisc/backend/attendance/entity/Attendance.java
+++ b/backend/src/main/java/org/sejongisc/backend/attendance/entity/Attendance.java
@@ -12,7 +12,6 @@
 
 @Entity
 @Getter
-@Setter
 @Builder
 @NoArgsConstructor
 @AllArgsConstructor
@@ -38,25 +37,32 @@ public class Attendance extends BasePostgresEntity {
     private AttendanceRound attendanceRound;
 
     @Enumerated(EnumType.STRING)
+    @lombok.Setter
     private AttendanceStatus attendanceStatus;
 
     @CreationTimestamp
     @Column(name = "checked_at")
+    @lombok.Setter
     private LocalDateTime checkedAt;
 
     @Column(name = "awarded_points")
+    @lombok.Setter
     private Integer awardedPoints;
 
     @Column(length = 500)
+    @lombok.Setter
     private String note;
 
     @Embedded
+    @lombok.Setter
     private Location checkInLocation;
 
     @Column(name = "device_info")
+    @lombok.Setter
     private String deviceInfo;
 
     @Column(name = "anonymous_user_name", length = 100)
+    @lombok.Setter
     private String anonymousUserName;
 
     // 지각 여부 계산 / 상태 업데이트
diff --git a/backend/src/main/java/org/sejongisc/backend/attendance/entity/AttendanceSession.java b/backend/src/main/java/org/sejongisc/backend/attendance/entity/AttendanceSession.java
index 5c08e17d..f5dc0801 100644
--- a/backend/src/main/java/org/sejongisc/backend/attendance/entity/AttendanceSession.java
+++ b/backend/src/main/java/org/sejongisc/backend/attendance/entity/AttendanceSession.java
@@ -5,7 +5,6 @@
 import lombok.*;
 import org.sejongisc.backend.common.entity.postgres.BasePostgresEntity;
 
-import java.time.LocalDateTime;
 import java.time.LocalTime;
 import java.util.ArrayList;
 import java.util.List;
@@ -50,7 +49,12 @@ public class AttendanceSession extends BasePostgresEntity {
     @Builder.Default
     private List<AttendanceRound> rounds = new ArrayList<>();
 
-    @OneToMany(mappedBy = "attendanceSession", cascade = CascadeType.ALL, fetch = FetchType.LAZY)
+    @OneToMany(mappedBy = "attendanceSession", cascade = CascadeType.ALL, fetch = FetchType.LAZY, orphanRemoval = true)
+    @JsonManagedReference
+    @Builder.Default
+    private List<SessionUser> sessionUsers = new ArrayList<>();
+
+    @OneToMany(mappedBy = "attendanceSession", cascade = CascadeType.ALL, fetch = FetchType.LAZY, orphanRemoval = true)
     @JsonManagedReference
     @Builder.Default
     private List<Attendance> attendances = new ArrayList<>();
diff --git a/backend/src/main/java/org/sejongisc/backend/attendance/entity/SessionUser.java b/backend/src/main/java/org/sejongisc/backend/attendance/entity/SessionUser.java
index 98c0c3c9..dc646e0b 100644
--- a/backend/src/main/java/org/sejongisc/backend/attendance/entity/SessionUser.java
+++ b/backend/src/main/java/org/sejongisc/backend/attendance/entity/SessionUser.java
@@ -1,10 +1,8 @@
 package org.sejongisc.backend.attendance.entity;
 
+import com.fasterxml.jackson.annotation.JsonBackReference;
 import jakarta.persistence.*;
-import lombok.AllArgsConstructor;
-import lombok.Builder;
-import lombok.Getter;
-import lombok.NoArgsConstructor;
+import lombok.*;
 import org.sejongisc.backend.common.entity.postgres.BasePostgresEntity;
 import org.sejongisc.backend.user.entity.User;
 
@@ -43,6 +41,7 @@ public class SessionUser extends BasePostgresEntity {
 
     @ManyToOne(fetch = FetchType.LAZY)
     @JoinColumn(name = "session_id", nullable = false)
+    @JsonBackReference
     private AttendanceSession attendanceSession;
 
     @ManyToOne(fetch = FetchType.LAZY)
@@ -50,6 +49,7 @@ public class SessionUser extends BasePostgresEntity {
     private User user;
 
     @Column(name = "user_name", length = 100, nullable = false)
+    @lombok.Setter
     private String userName;  // 저장 시점의 user.name 캐시 (나중에 user.name이 변경되어도 유지)
 
     /**