Abstract: Based on the study of robot subsystem of soccer-robot, a kind of compositive error model was set up by the analysis of wheeled-robot trajectory-tracking error. The design principles, arithmetic and implemental methods of cross-coupling tracking error compensator were presented based on fuzzy reasoning. By adding additional compensation on the input of speed loop of each wheel, the compensator can improve the trajectory tracking accuracy without changing the configuration of the robot inner-speed loop. The simulation was based on the mathematic model of soccer robot. The method can improve the trajectory tracking accuracy of wheeled robot effectively.