In this article, the similarity of stress field during landslide failure between inclined loading mode and prototype was researched. Numerical models of inclined loding mode and prototype were built, and the similarities of stress and strain field between the two models were observed.Failure approach index based on Mohr-Coulomb yield criterion was introduced to transfer the vector information of each element into scalar information so as to obtain the coefficient of correlation between the failure approach indexes of the two models. Hence the similarity of stress field during failure between the two models can be assessed. With Qianjiangping landslide as an engineering example, the change trend of failure approach index of the two models were verified to be close to each other. When reduction factor was 1.85 and inclination angle was [7°, 8.9°], the range of correlation coefficient was [0.7, 1.0], indicating that the failure stress fields of inclined loading mode and prototype were similar. The results suggest that inclined loading mode could well reflect landslide failure process.