Abstract: The main stream of the Jinsha River traverses the highly complex topography and intense neotectonic movement of the southeastern edge of the Qinghai-Tibet Plateau, where a large number of massive landslides have formed, resulting in severe landslide disasters in the region. Therefore, in-depth investigation into the formation mechanisms of these landslides along the main stream of the Jinsha River is of paramount significance for disaster prevention and mitigation in this area. This study conducts a comprehensive exploration of the formation mechanisms of these massive landslides using a combination of literature review and remote sensing image analysis. The findings reveal that the formation of massive landslides along the main stream of the Jinsha River is influenced by multiple factors. Firstly, topographical slope plays a crucial role, with a higher probability of landslide occurrence in the range of 25° to 40°. Secondly, active faults significantly contribute to the landslide formation process, as fault zone activity can lead to rock deformation and fragmentation, thus increasing the likelihood of landslide occurrence. Furthermore, the lithology of rock strata is also a key factor influencing landslides, impacting the physical and mechanical properties of rock-soil mass and the stress distribution characteristics of the slope, thereby resulting in regional stability differences and an increased potential for landslides. These factors can lead to further landslide development, and even trigger chain disasters such as river blockage, dam breach, and flooding in the basin.