To realize efficient walking and baiting operation in the grassy water environment of a crab pond, this paper designed a differential twin-body spiral drive device for a crab pond baiting boat, and studied its hydrodynamic performance based on CFD simulation technology. According to the demand for crab pond bait casting, the structure design and key parameter analysis of spiral driving devices are carried out. On this basis, based on Reynolds averaged Navier-Stokes(RANS) equation and SST K -ω turbulence model, a simulation model of the helical drive device was established by using unstructured tetrahedral mesh in Ansys, and the hydrodynamic performance of the helical blade was calculated and analyzed according to the two key parameters of height and pitch. The calculation results show that the jet velocity of the helical driving device increases with the increase of blade height, and the resistance is proportional to the pitch and blade height. At the same time, the hydrodynamic performance of the 200mm diameter driving device buoy increases greatly when the blade height is 60mm and the pitch is 255mm. Finally, a 4:1 prototype was used to verify the physical experiment. The error between the resistance at 600r/min and the simulation resistance was 4.72%, which verified the reliability of the simulation model. Therefore, the spiral drive device is a feasible and effective driving method for crab pond feeding vessels, and the proposed hydrodynamic performance analysis method can also provide a theoretical reference for the application of the spiral drive device in the water environment.