diff --git a/nflg_project_dev/nflg-bom-new/src/main/java/com/nflg/product/bomnew/service/domain/PBom/PBomUpgrade.java b/nflg_project_dev/nflg-bom-new/src/main/java/com/nflg/product/bomnew/service/domain/PBom/PBomUpgrade.java
index 443bdcca..b2a928ed 100644
--- a/nflg_project_dev/nflg-bom-new/src/main/java/com/nflg/product/bomnew/service/domain/PBom/PBomUpgrade.java
+++ b/nflg_project_dev/nflg-bom-new/src/main/java/com/nflg/product/bomnew/service/domain/PBom/PBomUpgrade.java
@@ -17,6 +17,7 @@ import com.nflg.product.bomnew.util.VersionUtil;
 import lombok.Getter;
 
 import java.time.LocalDateTime;
+import java.util.ArrayList;
 import java.util.List;
 import java.util.stream.Collectors;
 
@@ -30,10 +31,10 @@ public class PBomUpgrade {
     private List<BomNewPbomParentVO> allBom;
 
     @Getter
-    private List<BomNewPbomParentEntity> parentResult;
+    private final List<BomNewPbomParentEntity> parentResult = new ArrayList<>();
 
     @Getter
-    private List<BomNewPbomChildEntity> childResult;
+    private final List<BomNewPbomChildEntity> childResult = new ArrayList<>();
 
 
     public PBomUpgrade(BomNewPbomParentEntity root, List<BomNewPbomParentVO> allBom) {