The relative motion between plates leads to the formation and sliding of faults. Based on the velocity of plate movement and the geometric and physical properties of the 3 faults in Longmenshan, this paper simulates the sliding process of 3 faults in the Longmenshan fault zone for 600k years, and obtains 3 characteristics of the fault sliding in the Longmenshan fault zone: the first was the time segmentation feature, before 330k years of the plate movement, the three faults were locked; F3 fault was the fast slip stage between 330k and 370k years, with an average annual dislocation of 11mm; F3 fault was the stepped slip stage between 370k and 500k years; After 500k years, F1 and F2 fault begin to slip , which the slip vertical distance of F2 was 440m between 500k and 510k years, while began to slip at a steady rate of 3.3mm/yr after 500k years. The second was that F3 has stepped slip characteristics in a specific period, and the stepped slip has obvious periodicity, with a cycle of about 10k years, every step slip was completed in a very short time, and the vertical distance of the stepped slip was between 0.7-18.0m, with an average of 7.53m, which was similar to the current Longmenshan slip characteristics. The third was that the fault slip has the characteristics of "from deep to shallow, from local to whole" , the maximum slip of the three faults occurred in the middle and lower part, that is, the depth was between 10-30km, and the overall slip of the faults was gradually realized in the later stage.