With the development of Internet, privacy-preserving has become an increasingly prominent problem. Existing anonymous communication systems, such as Tor and Freenet, can conceal who communicate with whom. However they can't hide the fact that the users are using the anonymous communication technologies. File share software, such as BitTorrent and emule, has become the most popular application in Internet with users all over the world. In this paper, we present StegoP2P, a peer-to-peer based hidden communication method, which doesn't rely on a single system or a set of entry points. It is based on embedding the steganographic marker in the peer-to-peer meta-data exchange protocol, unlike other existing covert communication methods that rely on timing channel, and requires time synchronization. An efficient covert handshake protocol with steganographic marker techniques over peer-to-peer networks is proposed for unobservable communications, which allows users in peer-to-peer networks to exchange information secretly for circumventing Internet censorship. The steganography makes it easy for users to find the targeted content and difficult for a censor to identify them. Experimental results and security analysis show that our system has high performance and can defense against certain traffic censorships.