On April 20, 2013, a strong earthquake of M_s7.0 occurred at Lushan County, Sichuan Province of China. The earthquake triggered many landslides and some of the landslides resulted in serious hazards. In this paper, six earthquake-triggered landside impact factors, including the peak ground acceleration (PGA), the elevation, the slope angle; the slope aspect, the slope curvature, and the strata and lithology were selected for a GIS-based quick landslide susceptibility evaluation for the Lushan earthquake. The weights of the six factors and the landslide susceptibility ranks of each factor were assigned in an ordinal rating from 0 to 9 based on the expert knowledge and the information from my previous studies of the 2008 Wenchuan earthquake-triggered landslides. Then, the landslide susceptibility indexes of each grid were calculated and the landslide susceptibility index map of the study area was produced, which was validated based on 3878 landslides triggered by the Lushan earthquake with a success rate of the index map over 75%. This indicates that the method of the quick landslide susceptibility evaluation is reasonable and the result is useful. Finally, based on the landslide susceptibility index values, the study area was divided into five classes, namely the very low susceptibility, the low susceptibility, the moderate susceptibility, the high susceptibility, and the very high susceptibility, and the landslide susceptibility map was produced.