To study the surface electric field distribution of a converter valve tower in different structural designs in the VSC-HVDC transmission system, the electrostatic field of a converter valve tower is simulated using finite element ANSYS. First, the electric field distribution of the corona ring on the top is analyzed at different pipe diameters. It turns out to be similar under each pipe diameter, and there is no need to add a small corona ring inside the corner of the top corona ring. Then the electric field distribution of the plate and tubular shields is also studied. The two shielding systems both have good shielding ability to the valve tower, and the plate shielding system is slightly better than the tubular. Finally, the electric field distribution of the flange at the bottom of the valve tower is analyzed. The field is mainly concentrated at the bulge of the diagonal insulator connected to it. It provides accurate design ideas and detailed reference directions for the subsequent design of a converter valve tower in a VSC-HVDC transmission system. This work is supported by the Science and Technology Project of the Headquarters of the State Grid Corporation of China (No. 52110417001J).