Aiming at the problem of dynamic supervision and personnel rescue in the port water, based on catamaran, a USV with automatic stabilizing device and lifesaving equipment throwing device is designed. This paper expounds the function, mechanical structure and working principle of the USV. The results show that the USV can carry out planning waters patrol, clean water surface garbage, emergency and other tasks. With strong environmental adaptability and the navigation flexibility, it can be widely used in water environment management and personnel drowning rescue.