Abstract: According to the definite characteristics of the computer-supported cooperative design (CSCD) system, the characteristics of role delegation authorization (RDA) were analyzed and deduced, and a set of fitful status was found out. Because of the diversified characteristics of RDA features in different systems, the RDA model has multi-varying status. Introducing the basic model of role-based access control (RBAC), some basic characteristics of RDA was summed up. Then, the characteristics of RDA were recombined together according to the definite characteristics of CSCD system to develop a RDA model that is adaptable to CSCD system and different from the conventional role authorization models of RBAC, i.e., takes up the decentralized authorization management instead of centralized one in CSCD system to make it more flexible. This RDA model is verified through a CSCD example.