diff --git a/server/web3spider/tasks/bc_event_handlers/activate721nft.js b/server/web3spider/tasks/bc_event_handlers/activate721nft.js
deleted file mode 100644
index 74cebb5..0000000
--- a/server/web3spider/tasks/bc_event_handlers/activate721nft.js
+++ /dev/null
@@ -1,5 +0,0 @@
-class Activate721Nft {
-
-}
-
-module.exports = Activate721Nft;
diff --git a/server/web3spider/tasks/event_center.js b/server/web3spider/tasks/event_center.js
index 3efe791..bbccee7 100644
--- a/server/web3spider/tasks/event_center.js
+++ b/server/web3spider/tasks/event_center.js
@@ -9,9 +9,6 @@ const factory = require('./factory');
 
 class EventCenter extends BaseTask {
 
-  instances = [
-  ];
-
   async init() {
   }
 
@@ -23,7 +20,6 @@ class EventCenter extends BaseTask {
         instance['toBlock'] = 0;
         instance['currBlock'] = 0;
     };
-    const allInstances = [];
   }
 
 }