In order to further analyze the different factors affecting ship electric field and improve the accuracy of electric dipole modeling method in ship underwater electrostatic field simulation analysis. The corrosion electrochemical principle and characteristics of underwater corrosion electrostatic field are studied. The expression of galvanic corrosion current of ship-propeller is derived from the angle of corrosion current density. The analytical expressions of horizontal and vertical electric dipole electric field are solved by mirror image method under air-seawater two-layer model. The analytical model of the electric field based on the corrosion current dipole of the ship is established. On this basis, the electric field on the underwater 50 m line of a medium-sized ship is analyzed by numerical simulation. The results show that within the set range of variation, the influence degree of the corrosion potential of the hull and propeller, the immersion area of the hull and propeller, the seawater temperature and the seawater conductivity on the underwater corrosion electrostatic field of the ship are about 29%, 23%, 53%, 82%, 30% and 67%, respectively. The simulation results and the analytical model of the electric field can provide strong theoretical support for the further study of the electrostatic field characteristics and protection methods of underwater corrosion of ships.