diff --git a/src/main/java/com/interplug/qcast/biz/estimate/EstimateService.java b/src/main/java/com/interplug/qcast/biz/estimate/EstimateService.java
index b1e06fd0..7bbe4535 100644
--- a/src/main/java/com/interplug/qcast/biz/estimate/EstimateService.java
+++ b/src/main/java/com/interplug/qcast/biz/estimate/EstimateService.java
@@ -457,7 +457,6 @@ public class EstimateService {
               itemRequest.setItemCtgGr(itemResponse.getItemCtgGr());
               itemRequest.setPartAdd("0");
               itemRequest.setDelFlg("0");
-              itemRequest.setQcastCustPrdId(itemResponse.getQcastCustPrdId());
               break;
             }
           }
@@ -680,6 +679,13 @@ public class EstimateService {
             itemRequest.setObjectNo(estimateRequest.getObjectNo());
             itemRequest.setPlanNo(estimateRequest.getPlanNo());
 
+            // 선택한 PCS 아이템이 다른 경우
+            for (ItemRequest qcastCPI : itemList) {
+
+              if(qcastCPI.getQcastCustPrdId() != null && qcastCPI.getQcastCustPrdId().equals(itemRequest.getPcItemId())) {
+                itemRequest.setQcastCustPrdId(qcastCPI.getQcastCustPrdId());
+              }
+            }
             estimateMapper.insertEstimateRoofItem(itemRequest);
           }
         }
diff --git a/src/main/resources/mappers/estimate/estimateMapper.xml b/src/main/resources/mappers/estimate/estimateMapper.xml
index 35b0bbb2..288b815f 100644
--- a/src/main/resources/mappers/estimate/estimateMapper.xml
+++ b/src/main/resources/mappers/estimate/estimateMapper.xml
@@ -388,7 +388,7 @@
                     FROM T_PART_ROOF_ITEM_ESTIMATE (NOLOCK)
                     WHERE OBJECT_NO = PE.OBJECT_NO
                     AND PLAN_NO = PE.PLAN_NO
-                    AND PC_ITEM_ID = PE.ITEM_ID
+                    AND ISNULL(NULLIF(QCAST_CUST_PRD_ID, ''), PC_ITEM_ID) = PE.ITEM_ID
                   ), 0) AS MODULE_VOL_KW
             FROM T_PLAN P WITH (NOLOCK)
             INNER JOIN T_PART_ESTIMATE PE WITH (NOLOCK)