In order to study the motion control method suitable for the special characteristics of the unmanned catamaran, the application of fuzzy control technology in the motion control of speed and course is studied. The fuzzy controller of speed and course is constructed: the triangular membership function is selected in the speed fuzzy controller, the Gaussian membership function is selected in the course fuzzy controller; the rule base is formed according to human control experience; Mamdani method is selected as fuzzy inference method; area center of gravity method is selected as deblurring method. The simulation results show that the fuzzy control method is effective in the speed and course control of the unmanned catamaran.