Landslide is not only a direct disaster, but also can cause secondary disasters, huge surge formed by landslide body falling into the river will bring great harm. The surge height is affected by sliding speed, failure volume, water depth and other important factors; the formation of waves is affected by reservoir terrain, reservoir width, the duration of landslide falling into the reservoir and the width of landslide. Especially in the canyon area, in the wave propagation process, waves are also affected by the obstacles on both sides of the valley, round-trip refraction and wave group mutual interference or superposition. In this paper, Pan Jiazheng surge algorithm is used, under the condition of local landslide instability in Outang, the sliding velocity and surge height by landslide rushing into the reservoir are calculated and predicted; the earthquake action and the resistance of leading edge in reservoir water are considered.