Phone simulator is a simulation tool running on PC which can test debug phone software. It also provides front graphical user interface (GUI) like the true phone’s LCD. Developers can complete the initial development process and test work by phone simulator. This simulator is worked for mobile web application. It is different form traditional phone simulator. Traditional phone simulator only provided a simple runtime environment for application, they cannot imitate the real-world environment of mobile phone well, such as analog on device type, networking, memory size, device native APIs, PIM, runtime exceptions. This paper introduces our new simulator which is designed for mobile web application. For this purpose, a phone simulator based on Microsoft’s MFC library is developed. Experiment proved that it has significantly improved the speed of software development and test work. Keyword: device native ability, mobile network, mobile web application, simulator.