With the development of Information Communication Technique, electronic commerce using PKIs is widely used over the Internet. The goal of access control is to counter the threat of unauthorized operations involving Web-server or data base systems. The RBAC(Role-Based Access Control) has recently received considerable attention as a promising alternative to traditional discretionary and mandatory access controls. In this paper we propose two methods, the RBAC system using attribute certificates and the RBAC system using SPKI certificates. And we analyze and compare the two methods.