The present invention provides a method of web content filtering, which can be applied to gateway devices at client ends. When an access request for a web page from a browser is sent, by analyzing the web page content returned from the web site, we can decide whether the page is allowed or not, by early blocking and early bypassing algorithms. It allows making the decision as early as we have enough confidence that the web content should belong to some forbidden category or a normal one. Therefore, the web content determination speed can be improved and users' waiting time can be reduced. Moreover, by the present method, the network gateway devices will be allowed to analyze more web content.