The Mobile Social Network is particularly active at present in China. Its communicative characteristics are obvious. Users are always online，communication is decentralized，audience is more anti-popularization，information is fragmented and user-driven，user location is orientative. Mobile Social Networks enrich social forms，Social information is more real and abundant. The Mobile Social Network also has issues：Information overload，mobile phone dependency，insecure，and a risk to privacy. WeChat is only strongest status in the future. The competition among Mobile Social Networks is growing more fierce. Mobile Social Network with video and sounds is an advancing trend.