With the progress of peer-to-peer (P2P) technology, the Internet applications model is in a great reformation. In order to get an all-win solution among the Internet users, Internet service providers and content providers, it is necessary to measure and analyze the P2P applications from their perspectives. In this paper, the content of P2P measurement is introduced firstly, and then the existing research on P2P measurement is classified into 3 areas: topology measurement, traffic measurement and availability measurement. After comparing between measurement methods, the comprehensive survey on P2P measurement is given, and then the existing measurements and their results are analyzed in depth, furthermore, the shortcomings and problems are outlined. In the end, the future trend of the P2P measurement is discussed.