A dynamic access control method based on the community authorization service uses the role-based access control RBAC module scheme for reference and proposes a dynamic access control project based onthe community authorization service aiming at the dynamic characteristic of the grid computing environment. The method realizes the resource distribution, monitoring, dynamic access control, modification to the community authorization server and database to change the user role based on the context dynamic environment and realize the dynamic and transparent access to the resource in the gridding environment and seamless integration by interacting with the resource control module. The method can well solve the access control problem brought by dynamic character in the gridding environment and the transparent access to the resource.