Abstract: In order to solve the theoretical research on the reinforcement of landslide by short anti-sliding piles which does not match the needs of engineering application. Use FLAC^3D based on fast Lagrange algorithm to simulate the whole process of the reinforced gravel soil landslide with short anti-sliding piles with varying length. By analyzing the laws of displacement and stress of the sliding body, displacement and the bending moment of short anti-sliding piles, the mechanical deformation characteristics and pile-soil interaction mechanism of anti-sliding short piles are studied. The results show that reinforced by the short anti-sliding pile, the stability of the slope is increased obviously. The maximum displacement of slope is decreasing with the increasing length of short pile, but the range of decreasing is reducing. With the increase of pile length, the more uniform the stress distribution after pile, the better the integrity of short anti-sliding pile and soil around pile is, and the maximum displacement of sliding body decreases gradually, effectively inhibiting the displacement of sliding body. When the pile length is less than 60cm, "over the top" phenomenon occurs in the sliding body, and a penetrating sliding surface is formed at the top of the wedge's leading edge, and a small range of instability failure occurs. When the length of free segment of pile is 0.52~0.59 times of the sliding body thickness, the reinforcement effect is the best. The results of the study complement the anti-sliding mechanism of short anti-skid pile.