With the rapid development of mobile internet technology, Social Media has become an important way for us to communicate with others. Meanwhile, Social Media is regarded as the most popular information exchange and knowledge- sharing platformS by more and more people, making its network structure and information transmission topology attracted a wide attention. WeChat is one of the most commonly used Social Media in China, which was developed by Tencent in 2011. Due to the number of WeChat customer is very huge, traditional analytical methods become not applicable. In this paper, we try to use Social Network Analysis (SNA), which being capable of handling huge data, to reveal the relationship networks of WeChat. On this basis, we choose a WeChat user randomly, and listed part of groups that he participated in. Through analyzing its network architectures and data indicators, we found out three main information transmission topology of WeChat.