diff --git a/services/service/include/relationshipsyncmgr/relationship_sync_mgr.h b/services/service/include/relationshipsyncmgr/relationship_sync_mgr.h
index d0787d446100bd24d710f928f2ad4c4cd86a33fb..57900827e82936a898ee5c381422982fd36714f8 100644
--- a/services/service/include/relationshipsyncmgr/relationship_sync_mgr.h
+++ b/services/service/include/relationshipsyncmgr/relationship_sync_mgr.h
@@ -84,6 +84,8 @@ struct RelationShipChangeMsg {
     bool FromJson(const std::string &msgJson);
 
     const std::string ToString() const;
+    bool BuildCoreFields(cJSON *msg) const;
+    cJSON *BuildUdidArray() const;
 };
 
 class ReleationShipSyncMgr {
diff --git a/services/service/src/relationshipsyncmgr/relationship_sync_mgr.cpp b/services/service/src/relationshipsyncmgr/relationship_sync_mgr.cpp
index a676b056dac2e0b3fda7b1203dbfc0e7bd14d5bf..ec13afb68d427755de6c1ddfa09e350babe312d4 100644
--- a/services/service/src/relationshipsyncmgr/relationship_sync_mgr.cpp
+++ b/services/service/src/relationshipsyncmgr/relationship_sync_mgr.cpp
@@ -542,54 +542,86 @@ cJSON *RelationShipChangeMsg::ToPayLoadJson() const
     return arrayObj;
 }
 
-std::string RelationShipChangeMsg::ToJson() const
+cJSON *RelationShipChangeMsg::BuildUdidArray() const
 {
-    cJSON *msg = cJSON_CreateObject();
-    if (msg == NULL) {
-        LOGE("failed to create cjson object");
-        return "";
+    cJson *udidArrayObj = cJSON_CreateArray();
+    if (!udidArrayObj) {
+        LOGE("cJSON_CreatArray failed");
+        return nullptr;
+    }
+    
+    for (uint32_t index = 0; index < peerUdids.size(); index++) {
+        cJSON *udidStringObj = cJSON_CreateString(peerUdids[index].c_str());
+        if (!udidStringObj) {
+            LOGE("Create UDID string failed");
+            return nullptr;
+        }
+
+        if (!cJSON_AddItemToArray(udidArrayObj, udidStringObj)) {
+            LOGE("Add UDID to array failed");
+            cJSON_Delete(udidArrayObj);
+            cJSON_Delete(udidStringObj);
+            return nullptr;
+        }
     }
-    cJSON_AddNumberToObject(msg, MSG_TYPE, (uint32_t)type);
+    return udidArrayObj;
+}
+
+bool RelationShipChangeMsg::BuildCoreFields(cJSON *msg) const
+{
+    if (!cJSON_AddNumberToObject(msg, MSG_TYPE, (unit32_t)type)) {
+        LOGE("Add type failed");
+        return false;
+    }
+
     cJSON *arrayObj = ToPayLoadJson();
-    if (arrayObj == nullptr) {
-        LOGE("ArrayObj is nullptr.");
-        cJSON_Delete(msg);
+    if (!arrayObj) {
+        LOGE("Payload is nullptr");
+        return false;
+    }
+    if (!cJSON_AddItemToObject(msg, MSG_VALUE, arrayObj)) {
+        LOGE("Add Payload failed");
+        cJSON_Delete(arrayObj);
+        return false;
+    }
+    cJSON *udidArrayObj = BuildUdidArray();
+    if (!udidArrayObj) {
+        return false;
+    }
+    if (!cJSON_AddItemToObject(msg, MSG_PEER_UDID, udidArrayObj)) {
+        LOGE("Add UDID array failed");
+        cJSON_Delete(udidArrayObj);
+        return false;
+    }
+    if (!cJSON_AddStringToObject(msg, MSG_ACCOUNTID, accountName.c_str())) {
+        LOGE("Add account ID failed");
+        return false;
+    }
+    return true;
+}
+
+std::string RelationShipChangeMsg::ToJson() const
+{
+    cJSON *msg = cJSON_CreateObject();
+    if (!msg) {
+        LOGE("Creat root object failed");
         return "";
     }
-    cJSON_AddItemToObject(msg, MSG_VALUE, arrayObj);
 
-    cJSON *udidArrayObj = cJSON_CreateArray();
-    if (udidArrayObj == nullptr) {
-        LOGE("cJSON_CreateArray failed");
+    if (!BuildCoreFields(msg)) {
         cJSON_Delete(msg);
-        cJSON_Delete(udidArrayObj);
         return "";
     }
-    cJSON *udidStringObj = nullptr;
-    for (uint32_t index = 0; index < peerUdids.size(); index++) {
-        udidStringObj = cJSON_CreateString(peerUdids[index].c_str());
-        if (udidStringObj == nullptr || !cJSON_AddItemToArray(udidArrayObj, udidStringObj)) {
-            cJSON_Delete(udidStringObj);
-            cJSON_Delete(udidArrayObj);
-            cJSON_Delete(msg);
-            return "";
-        }
-    }
-    cJSON_AddItemToObject(msg, MSG_PEER_UDID, udidArrayObj);
-    cJSON_AddStringToObject(msg, MSG_ACCOUNTID, accountName.c_str());
+    
     char *retStr = cJSON_PrintUnformatted(msg);
-    if (retStr == nullptr) {
-        LOGE("to json is nullptr.");
-        cJSON_Delete(msg);
-        cJSON_Delete(udidArrayObj);
-        cJSON_Delete(udidStringObj);
+    if (!retStr) {
+        LOGE("Generate JSON string failed");
         return "";
     }
-    std::string ret = std::string(retStr);
+
+    std::string ret(retStr);
     cJSON_Delete(msg);
     cJSON_free(retStr);
-    cJSON_Delete(udidArrayObj);
-    cJSON_Delete(udidStringObj);
     return ret;
 }
 
@@ -697,5 +729,6 @@ void GetFrontAndBackUserIdInfos(const std::vector<UserIdInfo> &remoteUserIdInfos
         }
     }
 }
+
 } // DistributedHardware
 } // OHOS
\ No newline at end of file