diff --git a/js/dappModal.js b/js/dappModal.js
index f940c2e..8aebf26 100644
--- a/js/dappModal.js
+++ b/js/dappModal.js
@@ -50,18 +50,15 @@ const addWalletBtnListener = (walletConnector, end, onLoginSuccess) => {
     // add listener once
     $('#use-metamask-btn').click(() => {
         if (!(windowProvider && windowProvider.isMetaMask)) {
-            console.debug('Can\'t find MetaMask');
             myAlert.metamask();
             return;
         }
-        console.debug('Use MetaMask');
 
         window.ethereum = windowProvider;
         window.web3 = windowWeb3;
 
         modalStartLoading();
         window.ethereum.enable().then((res) => {
-            console.debug('res: ', res);
             modalHide();
             end(null, res);
         }).catch((err) => {
@@ -71,16 +68,13 @@ const addWalletBtnListener = (walletConnector, end, onLoginSuccess) => {
     });
     $('#use-dapper-btn').click(() => {
         if (!(windowProvider && windowProvider.isDapper)) {
-            console.debug('Can\'t find Dapper');
             myAlert.dapper();
             return;
         }
 
-        console.debug('Use Dapper');
 
         // Check if Dapper is unclocked
         if (!(windowWeb3.eth.coinbase)) {
-            console.debug('Dapper is locked');
             myAlert.dapperIsLocked();
             return;
         }
@@ -90,7 +84,6 @@ const addWalletBtnListener = (walletConnector, end, onLoginSuccess) => {
 
         modalStartLoading();
         window.ethereum.enable().then((res) => {
-            console.debug('res: ', res);
             modalHide();
             end(null, res);
         }).catch((err) => {
@@ -99,7 +92,6 @@ const addWalletBtnListener = (walletConnector, end, onLoginSuccess) => {
         });
     });
     $('#use-portis-btn').click(() => {
-        console.debug('Use Portis');
 
         const portis = new Portis('696237e9-38fb-406a-a4d6-bfa3a4d63293', config.network);
         const web3 = new Web3(portis.provider);
@@ -109,7 +101,6 @@ const addWalletBtnListener = (walletConnector, end, onLoginSuccess) => {
 
         modalStartLoading();
         window.ethereum.enable().then((res) => {
-            console.debug('res: ', res);
             modalHide();
             end(null, res);
         }).catch((err) => {
@@ -118,7 +109,6 @@ const addWalletBtnListener = (walletConnector, end, onLoginSuccess) => {
         });
     });
     $('#use-torus-btn').click(async () => {
-        console.debug('Use Torus');
 
         // Optional, if ture, reload or restore website will keep user web3 data
         // const isTorus = sessionStorage.getItem('pageUsingTorus');
@@ -152,7 +142,6 @@ const addWalletBtnListener = (walletConnector, end, onLoginSuccess) => {
         }
     });
     $('#use-ledger-btn').click(async () => {
-        console.debug('Use Ledger');
         showLedgerDerivationPath();
         $('#go-back').click(() => {
             ledgerPathGoBack();
@@ -167,7 +156,6 @@ const addWalletBtnListener = (walletConnector, end, onLoginSuccess) => {
             let accounts;
             try {
                 accounts = await web3.eth.getAccounts();
-                console.debug(accounts);
                 // Set default Account
                 const [firstAccount, ...rest] = accounts;
                 web3.eth.defaultAccount = firstAccount;
@@ -191,7 +179,6 @@ const addWalletBtnListener = (walletConnector, end, onLoginSuccess) => {
             let accounts;
             try {
                 accounts = await web3.eth.getAccounts();
-                console.debug(accounts);
                 // Set default Account
                 const [firstAccount, ...rest] = accounts;
                 web3.eth.defaultAccount = firstAccount;
@@ -230,7 +217,6 @@ const addWalletBtnListener = (walletConnector, end, onLoginSuccess) => {
         }
     });
     $('#use-mobile-btn').click(() => {
-        console.debug('Use WalletConnect');
 
         if (window.isMobile) { // Mobile
             myAlert.wcUnsupport();
@@ -247,7 +233,6 @@ const addWalletBtnListener = (walletConnector, end, onLoginSuccess) => {
                 const { uri } = walletConnector;
                 // display QR Code modal
                 WalletConnectQRCodeModal.open(uri, () => {
-                    console.debug('QR Code Modal closed');
                 });
             });
 
@@ -290,7 +275,6 @@ module.exports = {
 
             // Add dismiss handler
             const listener = () => {
-                console.debug('On dappQrcodeModal close');
                 $('#dappQrcodeModal').off();
             };
             $('#dappQrcodeModal').on('hidden.bs.modal', listener);
diff --git a/js/dappSdkProvider.js b/js/dappSdkProvider.js
index b8e060d..0138a64 100644
--- a/js/dappSdkProvider.js
+++ b/js/dappSdkProvider.js
@@ -17,10 +17,8 @@ RemoteLoginSubprovider.prototype.handleRequest = function handleRequest(payload,
     switch (payload.method) {
         // enable
         case 'eth_requestAccounts': {
-            console.debug('******* enable(), eth_requestAccounts *******');
             const { payload: { walletConnector } } = payload;
 
-            console.debug(walletConnector);
 
             dappModal.showLoginQrcodeWithString(
                 walletConnector,
@@ -36,13 +34,11 @@ RemoteLoginSubprovider.prototype.handleRequest = function handleRequest(payload,
         }
 
         case 'eth_coinbase': {
-            console.log('eth_coinbase');
             end(null, self.defaultAddress);
             break;
         }
 
         case 'eth_accounts': {
-            console.log('eth_accounts');
             end(null, [self.defaultAddress]);
             break;
         }
@@ -53,17 +49,14 @@ RemoteLoginSubprovider.prototype.handleRequest = function handleRequest(payload,
             }
 
             const txData = payload.params[0];
-            console.log('eth_sendTransaction txData: ', txData);
             self.walletConnector
                 .sendTransaction(txData)
                 .then((result) => {
                     // Returns transaction id (hash)
-                    console.log('result: ', result);
                     end(null, result);
                 })
                 .catch((error) => {
                     // Error returned when rejected
-                    console.log('error: ', error);
                     end(error);
                 });
             break;
@@ -74,7 +67,6 @@ RemoteLoginSubprovider.prototype.handleRequest = function handleRequest(payload,
                 end(Error('Please login.'));
             }
 
-            console.log(payload.params);
             const { params: [address, data] } = payload;
             const msgParams = [
                 address,
@@ -83,12 +75,10 @@ RemoteLoginSubprovider.prototype.handleRequest = function handleRequest(payload,
             self.walletConnector.signMessage(msgParams)
                 .then((result) => {
                     // Returns signature.
-                    console.log('result: ', result);
                     end(null, result);
                 })
                 .catch((error) => {
                     // Error returned when rejected
-                    console.log('error: ', error);
                     end(error);
                 });
             break;
@@ -112,12 +102,10 @@ RemoteLoginSubprovider.prototype.handleRequest = function handleRequest(payload,
             self.walletConnector.signPersonalMessage(msgParams)
                 .then((result) => {
                     // Returns signature.
-                    console.log('result: ', result);
                     end(null, result);
                 })
                 .catch((error) => {
                     // Error returned when rejected
-                    console.log('error: ', error);
                     end(error);
                 });
             break;
diff --git a/js/index.js b/js/index.js
index b3c818d..7077031 100644
--- a/js/index.js
+++ b/js/index.js
@@ -16,7 +16,6 @@ let _defaultAddress;
 const { rpcUrl } = config;
 
 const getDefaultAddress = () => {
-    console.log('getDefaultAddress');
     if (_defaultAddress !== undefined) {
         return _defaultAddress;
     }
@@ -24,7 +23,6 @@ const getDefaultAddress = () => {
 };
 
 const getNetVersion = () => {
-    console.log('getNetVersion');
     return 1;
 };
 
@@ -75,7 +73,6 @@ const initEngine = () => {
     eng.dappSdk = { version };
 
     eng.enable = async (cb = () => {}) => {
-        console.log('enable');
         const p = new Promise((resolve, reject) => {
             const rpcData = {
                 method: 'eth_requestAccounts',
@@ -85,10 +82,8 @@ const initEngine = () => {
             };
             eng.sendAsync(rpcData, (err, res) => {
                 if (err) {
-                    console.log('enable rejected with err: ', err);
                     reject(err);
                 }
-                console.log('enable resolved, res: ', res);
                 defaultEnableCallback(err, res);
                 cb(err, res);
                 resolve(res);
diff --git a/js/staticProvider.js b/js/staticProvider.js
index c241bdd..b8fb92b 100644
--- a/js/staticProvider.js
+++ b/js/staticProvider.js
@@ -8,15 +8,12 @@ function StaticProvider(defaultAddressGenerator, defaulNetVersionGenerator) {
 
     self.staticResponses = {
         eth_accounts: () => {
-            console.log('****eth_accounts');
             return [self.defaultAddressGenerator()];
         },
         eth_coinbase: () => {
-            console.log('****eth_coinbase');
             return self.defaultAddressGenerator();
         },
         net_version: () => {
-            console.log('****net_version');
             return self.defaulNetVersionGenerator();
         },
     };
@@ -31,13 +28,11 @@ StaticProvider.prototype.handleRequest = function handleRequest(payload, next, e
 
 StaticProvider.prototype.handleSyncRequest = function handleSyncRequest(payload) {
     const self = this;
-    console.log('payload.method: ', payload.method);
     const staticResponse = self.staticResponses[payload.method];
     if (typeof staticResponse === 'function') {
         return staticResponse();
     // static response - null is valid response
     } if (staticResponse !== undefined) {
-        console.log(staticResponse);
         return staticResponse;
     // no prepared response - skip
     }
diff --git a/js/walletConnect.js b/js/walletConnect.js
index ec6dbad..ab0b519 100644
--- a/js/walletConnect.js
+++ b/js/walletConnect.js
@@ -8,7 +8,6 @@ const setupWalletConnector = (walletConnector) => {
 
         // Get updated accounts and chainId
         const { accounts, chainId } = payload.params[0];
-        console.debug('on session_update', accounts, chainId);
     });
 
     walletConnector.on('disconnect', (error, payload) => {
@@ -17,7 +16,6 @@ const setupWalletConnector = (walletConnector) => {
         }
 
         // Delete walletConnector
-        console.debug('on disconnect');
         // eslint-disable-next-line no-alert
         alert('Log out successfully.');
         // eslint-disable-next-line no-restricted-globals
diff --git a/sample/sample.html b/sample/sample.html
index 577de4f..5443922 100644
--- a/sample/sample.html
+++ b/sample/sample.html
@@ -177,7 +177,6 @@ <h5 class="card-title">ETH Amount</h5>
         alert('Please use wallet connect.');
     } else {
         window.ethereum.logout().then((res) => {
-            console.log('logout done. res: ', res);
         }).catch((err) => {
             alert(err);
         });
diff --git a/sample/server.js b/sample/server.js
index 785a330..c127f81 100644
--- a/sample/server.js
+++ b/sample/server.js
@@ -7,10 +7,8 @@ var path = require('path');
 function start(route) {
 	var app = express();
 
-	console.log('Server start...');
 
 	app.get('/', (req, res) => {
-    	console.log("Request received.");
 		fs.readFile('./sample/sample.html',(err, data) => {
 			res.writeHead(200, {"Content-Type": "text/html", 'Content-Length':data.length});
 			res.write(data);