It has great importance in the establishment of tropical cyclone retrieval and analysis WebGIS system. Flex is one of the most popular rich client technologies which is invented by the Adobe company. It is an efficient,open source and cross platform framework,it combines the rich expressiveness of desktop software and ease of use of Web program. According to the mass,distribution,archiving and strong temporal characteristics of tropical cyclone spatial data, the western north pacific ocean tropical cyclones retrieval and analysis WebGIS system is developed based on the Flex and REST architecture. System provides multi-source data retrieval and analysis functions for the forecasters. It improves the capacity of prevention and mitigation of disasters.