A kind of hierarchical and distributed multi-agent proactive security defense framework based on trusted computing is proposed by combining information security with an analysis of business and algorithm. First， the characteristics of network attack and the causes of security threats are analyzed. Then the structure of the security defense framework is given， including the transport layer， access authority layer， platform authentication layer and advanced trusted behavior analysis layer. Some key techniques and strategies are studied， such as the check of user access authority， digital association， behavior analysis of network and business. The trusted system provides control for the suppression of network attacks and other suspicious events. A preliminary security design is implemented for a kind of wide-area backup protection system. The tests on the processing time for encryption algorithms are performed.