diff --git a/features/udm_user/service/service_udm_sub_user.go b/features/udm_user/service/service_udm_sub_user.go
index f1c54abb..3bd72ca2 100644
--- a/features/udm_user/service/service_udm_sub_user.go
+++ b/features/udm_user/service/service_udm_sub_user.go
@@ -83,7 +83,7 @@ func (r *ServiceUdmSubUser) Inserts(neID string, subUser model.UdmSubUser, num s
 		subUser.Imsi = imsi
 
 		// IP会自动递增
-		if subUser.StaticIp != "" {
+		if len(subUser.StaticIp) > 5 {
 			parts := strings.Split(subUser.StaticIp, ".")
 			lastPart := parts[3]
 			lastNum, _ := strconv.Atoi(lastPart)