Abstract: Proportion-Integration-Differentiation (PID) control algorithm is used in the iteration of the tilt attitude and pivot film thickness of tilt pad thrust bearings for solving Reynold equation. The equilibrium of force and moment were achieved simultaneously. Numerical examples were given with the smooth and the roughness pad surfaces calculated by PID and traditional method separately. The result indicates that the efficiency and convenience of PID method. The characteristics of stiffness of tilt pad thrust bearings was also given. The PID method can solve the convergence problem induced by surface roughness of traditional method.