WebGIS currently has a wide range of application requirements and can generate greater economic value. Therefore, there are many units that need to build their own WebGIS system. At present, the way to build a system is usually to purchase professional software and hire professionals to complete the development. Such a construction method requires a high cost, and many of the WebGIS system applications are the same or similar, and repeated construction is also a waste of resources. In order to solve this problem, a WebGIS system based on edge computing is proposed. Comprehensive use of SAAS mode and edge computing methods to solve the needs of users can customize the system. And the system load is reasonably distributed between the server and the browser, which improves the performance of the system. In addition, the system uses edge computing to share map tiles among WebGIS users, reducing the pressure on the server and increasing the speed of use of the WebGIS system. Therefore, the WebGIS system based on edge computing can not only be personalized and customized, but also has good usability and can deal with a large number of visits. After experimental verification, in the case of more than 5 concurrent user requests per second, the system response speed increased by more than 38.6%.