In order to efficiently carry out water treatment, a catamaran-type water surface garbage cleaning robot based on water fluidity is designed. The function, mechanical structure and working principle of the robot are described in detail. It mainly relies on the submersible pump to provide power to form a local water flow to drive the garbage into the garbage cleaning cabin to clean up the garbage. The results show that the robot is suitable for a variety of complex water environments. It has advantages of strong stability, high operating efficiency, environment-friendly raw materials and environmental protection and can be widely used in the field of water treatment.