The Robot World Cup is the largest mobile robot event and the most important international conference on AI and robotics at present. RoboCup is an attempt to promote AI and robotics research by providing a common task for evaluation of various theories, algorithms, and agent architectures. This paper studies the theoretical and technical issues of the application of the expert system for robot planning theory to RoboCup. This paper gives a primary introduction of the expert system and the robot planning, the content includes the theory of the robot planning based on expert system and the framework of the system that based on the theory. Finally, its application of the framework to RoboCup and how machine learning can be integrated in the system are also studied in this paper.