Abstract: One fundamental purpose of Tencent introducing WeChat is to provide a dating platform, so WeChat highlights strong social function in the communication activities. As a free social tool, WeChat is favored by college and university students who haven't independent economy ability, are spiritual hunger and interested in friends. They receive and send short messages, upload video, audio, picture and so on. At the moment of shining mood and exposure life, they show their ideology dynamic. This essay analyzes the character of ideology dynamic of college and university students which WeChat reflects based on social function, then proposes relevant countermeasure, and investigate the specific ways of using the social function of WeChat to do ideological and political work better.