Peer-to-peer systems let users share information in distributed environments because of their scalability and efficiency. However, existing P2P systems are vulnerable to numerous security attacks and lack a mechanism to ensure shared information?s authenticity and integrity. A proposed general architecture enhances these aspects by leveraging trusted computing technology, which is built on a trusted platform module and provides a mechanism for building trust into theapplication layer. Preliminary experimental results show that the proposed scheme can ensure data authenticity and integrity in P2P systems with acceptable performance overhead.