Volume and topography are two important factors affecting runout distance of landslides. On the basis of detailed field investigation of the landslides triggered by “5.12 ” Wenchuan earthquake, the relationships between runout distance and landslide volume and initial slope angle for 46 typical earthquake-induced landslides were analyzed. The results show that there are good exponential relationships between the logarithmic values of displaced volume and horizontal and vertical distances for the landslides, and the R2 values are 0.8244 and 0.7859 respectively. Moreover, there is an good linear relationship between the equivalent friction coefficient and tangent values of initial slope angle for the landslides, and the R2 values is 0.7973. In addition, a relation of horizontal(Lr) and vertical distance(H), landslide volume(V) and initial slope angle(θ) for the landslides, was obtained by binary linear regression, with the equation of logLr=-0.0785logV+1.2347log(H/tanθ).
