Based on the theory of privacy calculus and technology acceptance model (TAM), the study constructed the theoretical model on the impact factors of the information disclosure willingness of mobile social platform users. The study did the empirical study using Wechat, and chose activate Wechat users to do the research. The results showed that:perceived usefulness, perceived ease of use are positively related to the mobile social platform user information disclosure willingness , while privacy concerns is negative related to it;compared to the perceived ease of use and privacy concerns, perceived usefulness of information disclosure for users of mobile social platform is more significant;the moderating effect of privacy concerns for perceived usefulness, perceived usefulness and information disclosure willingness is not significant.