The interaction between wave and superstructure is very complicated, and there is no calculation basis in the current design codes. In this case, when the high-pile wharf is designed, the formula of wave force to the high-pile wharf superstructure, which is in the Handbook for Design of Sea Harbour Structure, is usually adopt. According to the handbook formula, this paper proposes to adopt the graphical calculation method of using AutoCAD to draw the theoretical wave surface. By adjusting the relative position between wave surface and wharf structure across-section, an engineering example is calculated in different working conditions, to serve as reference for the engineering design.