Grid provides people the way to share large mount of distributed resources and services that belong to different local organizations. That is a good way to share many kinds of distributed resources via the network in the open environment, thus it makes security problems more complicate and more important for us than before. In this paper, we analyze the requirements of trusted computing in grid. Considering the security and safety problems both in software and hardware, we construct a way to promote the trusted computing environment for grid by integrating the trusted computing platform (TCP) into grid system. We propose a new prototype system, the Daonity, in which grid system is combined with Trusted Platform Support Service (TSS) and TSS is based on Trusted Platform Module (TPM). In this design, better effect can be obtained in authentication, confidentiality and integrity in grid computing environment.