diff --git a/server/web3dbspider/services/dbevent_process.js b/server/web3dbspider/services/dbevent_process.js
index dcc2c18..9eb9adf 100644
--- a/server/web3dbspider/services/dbevent_process.js
+++ b/server/web3dbspider/services/dbevent_process.js
@@ -92,7 +92,7 @@ class DbEventProcess extends BaseService {
           this.getContractAddress()
         ]);
       if (err) {
-        throw err;
+        throw new Error(err);
       }
       if (rows.length > 0) {
         this.progInfo['procEventCount'] += rows.length;