Cloud is a computing model that provides sharing and supports ubiquitous on-demand access computing, providing new data processing and services for many industries, significantly reducing user computing and storage costs, and improving ease of use. With the development of cloud-scale and intensification, cloud security has become an essential issue in the field of cloud computing. Access control is one of the critical security technologies for protecting sensitive data stored in the cloud by enterprises and individuals. Since the centralized access control mechanism is adopted in the cloud, the sensitive data in the cloud are easy to be tampered with or leaked by hackers or cloud internal managers. This project proposes, a block chain-based access control framework with privacy protection called AuthPrivacy Chain. Firstly, we use the account address of the node in block chain as the identity, and at the same time, redefine the access control permission of data for the cloud, which is encrypted and stored in block chain. After that, we design processes of access control, authorization, and authorization revocation in AuthPrivacy Chain. Finally, we implement AuthPrivacy Chain based on enterprise operation system (EOS), and the results show that AuthPrivacy Chain can not only prevent hackers and administrators from illegally accessing resources, but also protect authorized privacy.