Abstract: The complex adaptive system （CAS） is a hot research topic. It is useful for the experts to have a general distributed simulation platform. In this paper, the CAS is discussed deeply firstly. And then the structural characteristics of CAS are defined formally, which include the notations such as object component, adaptive agent component, message, inherence and aggregation. According to this comprehension of CAS, a distributed simulation framework is proposed. The public service agent such as global service agent and local service agent, and adaptive agent in the framework are described in detail especially. Finally, the logic structure of the framework is given. Compared with other platforms, it has many advantages.