We can receive large information from various web sites using the Internet. The web sites are important means to collect the required information in researching, learning, and even in commerce activities. Importance of web browsers grows increasingly as web sites increase. Web browsers are powerful tools to refer to web sites. However, due to necessary of synchronous communication with web servers, operationality of web pages on web browser is not better than operationality of desktop applications. Therefore, we propose a new web browser for Ajax approach with asynchronous communication model. Our web browser can improve the operationality that is equivalent to the operationality of desktop applications without revising program codes of the web applications. A feature of the browser is partial updating of a web page even if the web application does not adopt Ajax approach. As a result of experiments, we have confirmed improvement of operationality of "Yahoo auction sites" on our web browser when the load of the web server increases.