Abstract: Jinsha River, upper reach of Changjiang River, is located in the transition zone of the southeast Qinghai-Tibet Plateau, Yunnan-Guizhou Plateau and Sichuan Basin. In this area, geological environment is variable with intense neotectonics movement, fragile ecosystem and frequent landslides. In order to study the occurrence and distribution characteristics and its influencing factors, we take Suwalong-Benzilan reach of the Jinsha River as a case study. Through field geological investigations and existing data, we analyze 32 landslides in the reach. The research results are shown as follows: 1) the spatial distribution of landslide is uneven, mainly in four regions, namely Wangdalong, Maoding, and Simuda in the mainstream of Jinsha River, and Guxue township in the branch of Jinsha River; 2) landslides are mainly huge and large-scale types whose attitudes are in agreement with deep bedrock, but few landslides exist in quaternary deposits;3) landslides at Suwalong-Benzilan reach of the Jinsha River formed in earlier geological ages, and elevation of shear outlet of the landslides is higher than that of water level of the river due to intensive neotectonic movement and rapid river incision rate; 4) landslide is relevant to geological environment conditions such as landform, lithologic character, geologic structure and river bank structure, in particular, landslide disasters easily occur in conditions of mountain bodies with 30° to 35°slope gradient, greenschist and ophiolite rock mass, fault areas within 1 kilometer and normal river bank slopes.

Key words: Suwalong-Benzilan reach, landslide hazard, occurrence characteristics, influencing factors, Jinsha River