Electric field measurements in seawater will affect the target electric field. In order to improve the accuracy of the electric field measurement, the influence factors of the object on distribution of the electric field in seawater were studied by the finite element method, and the distribution law of the distortion electric field was determined. The simulation results show that the magnitude of the distortion peak and the distortion area are affected by the conductivity and shape of the object. When the conductivity of the object is smaller or larger than that of the seawater, the effect on the electric field distribution is on the opposite:the larger the curvature of the object is, but the larger the peak value of the distortion is, but the smaller the distortion area is.