On the trusted domain, the large number of subjects, many types of objects, complex and volatile environment, which give a challenge to the traditional access control. The traditional access control policy is not flexible enough and difficult to achieve fine-grained permissions. To the problems of which, proposes a dynamic and Fine-Grained Access Control method. The method bases on RBAC and increases the constraint condition on the RBAC model.During its implementation.PEP Fine-Grained component is increased. The method reflects the dynamic and fine-grained of the access, meets the access control requirement of the dynamic and Fine-Grained Access Control.