Combining the pseudo dynamic method with the limit equilibrium three-dimensional Spencer method, the calculation formulas for seismic force and safety factor are derived, and corresponding calculation programs are written. A three-dimensional slope stability analysis method considering wave effects is established, and the correctness of the method and program is verified through numerical examples. This method was used to analyze the influence of geometric parameters, soil parameters, and wave effects on the pseudo dynamic and pseudo static safety factors of slopes, as well as the difference between the two. The research results show that the safety factor decreases with the increase of slope height, slope angle, and failure surface width, and the pseudo dynamic safety factor is always greater than the pseudo static safety factor. The difference between the two increases with the increase of slope height and decreases with the increase of slope angle and failure surface width; The safety factor increases with the increase of cohesion and internal friction angle, and the pseudo dynamic safety factor is always greater than the pseudo static safety factor. The difference between the two increases with the increase of cohesion and internal friction angle; The safety factor increases with the increase of ground vibration coefficient, and the pseudo dynamic safety factor is always greater than the pseudo static safety factor. The difference between the two increases with the increase of ground vibration coefficient.