RoboCup is designed to evaluate various theories, algorithms, and architectures for new challenges of Artificial Intelligent (AI) research. New challenges will import new functions into a soccer robot. Thus, a soccer robot with modularized control circuits is proposed to conveniently add new functions for further challenges. At present, the designed soccer robot, based on circuit function, has five modules: processor module, radio communication module, input/output module, supersonic module and extensible module. Five modules are together connected via Industry Architecture Standard bus (ISA bus) in extensible module. In addition, the motion planning of a soccer robot for kicking the ball is formularized to shoot goal. Experiment is also included.