A web browser system includes a mobile communication terminal configured to implement decoding and parsing for HTML and CSS binary files, execute a JavaScript bytecode, decode an image file, and implement rendering for respective results, for web browsing of a web browser built therein; a proxy server configured to, in correspondence to a web address transmitted thereto, transmit a page access command to a web server of the corresponding web address via a wired network, implement grammar indentifying binary encoding for HTML and CSS transmitted from the web server to decrease capacity, convert quality for an image file to decrease capacity, compile JavaScript into a bytecode to decrease capacity, and transmit those files to the mobile communication terminal via a wireless network; and a web server configured to transmit files constituting a web page including the HTML, CSS, JavaScript and image files, to the proxy server.