Mobile Social Networks (MSN) are attractive applications which enable users to share data with a group of friends and stay connected. WeChat, QQ are among the most popular applications of MSNs where personal multimedia files are shared among group contacts. However, the security risks accompanying such developments have raised concerns in people. The providers typically store users’ data, and offer few options for the users to custom and manage the dissipation of their data over the network. In this paper, we design a data sharing framework in which individuals retain ownership of their data. The scheme gives users flexible and granular access control over their data, and more importantly it provides protection from the untrusted data provider server. Experiments show the efficiency of our scheme.