Abstract: Through analyzing the goal and environment of software evolution process,binding the goal,environment and corresponding software evolution process’s activities,this paper put forward a kind of goal-directed software evolution process model,and used it to guide the modeling.In this model,the guidance of modeling was the evolution goal.The process’s behavior could be identified according to the goals and resources.In this paper it described the process behavior using communication sequential process,discused the compute of process’s recourses,transit of goal’s state and the priority of goal deeply.