In this paper security requirements and security architecture for 4G systems are presented with the consideration of Trusted Computing (TC) for mobile equipment (ME). The security framework based on Trusted Mobile Platform (TMP) and PKI is proposed to provide a considerable robust platform for user’s access to sensitive service and data in the scenario of 4G systems. Over this framework, with the combination of password and biometric identification (BI) as well as public key-based identification, an efficient hybrid authentication and key agreement (HAKA) scheme is presented to resist the possible attacks, particularly the attacks on/from ME. Compared with 3G architecture and other security schemes for 4G mobile networks, our architecture and corresponding HAKA is more secure, scalable and convenient to support globe mobility and capable of being employed to handle the complicated security issues in 4G mobile networks.