Aiming at solving the “snap back” problem in the stiction, the sine rough surface model is established. Based on the Casimir effect, the Casimir force is obtained. Based on the micro scopic Wigner-Seitz principle, the Hanaker force is derived, which includes the repulsive force. The stiction force is simulated and the two “snap back” points are found. The curve of the stiction force has two break points, which is in agreement with the experiment.