Cloud computing security has become a key problem of restricting the development of cloud computing, solving the cloud computing security problem has been extremely urgent. At present, it has become a new favorite in the cloud computing security research field that trusted computing is used to solve the cloud computing security, this paper uses remote attestation in trusted computing to solve the cloud computing security problems. In a cloud computing environment, the service provider not only needs to provide reliable components, but also needs to ensure that the computing platform system is reliable. In this paper, in view of the characteristics of the cloud computing platform, these two approaches are consolidated and improved, and a proof method based on the component properties and the system behavior (CPTBA) is put forward.