diff --git a/src/ExtensionAPI.js b/src/ExtensionAPI.js
index c094f2b8bc779d89f35458203705c361a11d9b81..cc7a79bd0b9c7f3e4001ddd99ca39e75ad200b75 100644
--- a/src/ExtensionAPI.js
+++ b/src/ExtensionAPI.js
@@ -13,64 +13,7 @@ define(function(require) {
         zrUtil.each(echartsAPIList, function (name) {
             this[name] = zrUtil.bind(chartInstance[name], chartInstance);
         }, this);
-
-        // Namespace used for extensions, including builtin components
-        this._namespaces = {
-            // Default echarts namespace
-            echarts: {}
-        };
-
-        this._defaultNS = 'echarts';
     }
 
-    var extensionProto = ExtensionAPI.prototype;
-
-    /**
-     * Create a namespace for extension or component
-     * @param {string} ns
-     */
-    extensionProto.createNamespace = function (ns) {
-        this._namespaces[ns] = {};
-    };
-
-    /**
-     * Set default namespace
-     * @param {string} ns
-     */
-    extensionProto.useNamespace = function (ns) {
-        this._defaultNS = ns;
-    };
-
-    /**
-     * Get value from namespace
-     * @param {string} key
-     * @param {string} [ns] Use default namespace defined by useNamespace
-     */
-    extensionProto.get = function (key, ns) {
-        ns = ns || this._defaultNS;
-        return this._namespaces[ns] && this._namespaces[ns][key];
-    };
-
-    /**
-     * Put value to namespace
-     * @param {string} key
-     * @param {*} val
-     * @param {string} [ns] Use default namespace defined by useNamespace
-     */
-    extensionProto.put = function (key, val, ns) {
-        ns = ns || this._defaultNS;
-        if (this._namespaces[ns]) {
-            this._namespaces[ns][key] = val;
-        }
-    };
-
-    /**
-     * Dispose namespace
-     * @param {string} key
-     */
-    extensionProto.disposeNamespace = function (ns) {
-        delete this._namespaces[ns];
-    };
-
     return ExtensionAPI;
 });
\ No newline at end of file