Fast catamaran holds excellent performance because of its high transverse stability, large deck, economy of fuel consumption and high speed. However, the high-speed craft can easily make "twist" oscillation in moderate to rough sea conditions due to its low length to beam ratio and relatively lightweight. T-foils or interceptors are effective stabilizers for alleviating the pitch and heave motions of fast craft. This work designs an autonomous catamaran motion control system utilizing 2 T-foils and 2 interceptors, which can not only control the longitudinal motion, but also alleviate the roll motion of fast catamaran. Numerical simulation results show that the motion control system can satisfactorily improve sea keeping performance of fast catamaran.