diff --git a/src/main/java/com/ai/da/service/impl/MessageCenterServiceImpl.java b/src/main/java/com/ai/da/service/impl/MessageCenterServiceImpl.java
index b5e5a4f4..bff32d27 100644
--- a/src/main/java/com/ai/da/service/impl/MessageCenterServiceImpl.java
+++ b/src/main/java/com/ai/da/service/impl/MessageCenterServiceImpl.java
@@ -135,7 +135,7 @@ public class MessageCenterServiceImpl extends ServiceImpl<NotificationMapper, No
                     notificationVO.setIsRead(1);
                 }
             }else {
-                String avatar = StringUtil.isNullOrEmpty(senderAccount.getAvatar()) ? CommonConstant.DEFAULT_AVATAR : senderAccount.getAvatar();
+                String avatar = Objects.isNull(senderAccount) || StringUtil.isNullOrEmpty(senderAccount.getAvatar()) ? CommonConstant.DEFAULT_AVATAR : senderAccount.getAvatar();
                 notificationVO.setAvatar(minioUtil.getPreSignedUrl(avatar, CommonConstant.MINIO_IMAGE_EXPIRE_TIME));
             }
             return notificationVO;