A method for an HTML document to access local system resources, which receives an HTTP request and judges whether the HTTP request includes a predetermined keyword. A system-resource-accessing portion of the HTTP request is processed when the HTTP request includes the predetermined keyword. Then, the HTTP request is checked whether it contains a Referer field. If the header of the HTTP request includes the Referer field, the HTTP request will be treated as an external request, and the local system resource accessing will be denied even when the HTTP request includes the predetermined keyword.