To study the generation mechanism and variation law of ship electric field under navigation conditions, combining electrochemical principles and fluid dynamics related theories, analyzing the theoretical basis of multi-physics modeling such as turbulent flow field and ship electric field, and combining the equivalent resistance change law of the ship shafting mechanical structure in the axial frequency electric field, finally adopts the boundary element method Establish a submarine corrosion mixed electric field model under turbulent medium conditions, and analyze the changes of the ship′s electrostatic field and axial frequency electric field under different propeller speeds and medium flow rates. The results show that when the propeller speed increases from 0 to 1,2, 3,4, the electrostatic field of the ship at 2B(B is breadth of ship) directly below the propeller increases by 66.5%, 13%,3.7%, and 1.19%, and the frequency of the mixed electric field is consistent with the propeller speed. This model provides a theoretical reference for analyzing the changing law of the mixed electric field of a ship in motion.