<p>This study employs the discrete element method (DEM) to simulate the dynamic processes of landslides induced by rainfall and earthquakes, with the objective of conducting a comprehensive investigation into the influencing factors, failure mechanisms, energy transformation, and movement characteristics of landslides. The methodology employed involved the construction of a two-dimensional landslide model, which was utilized for simulating the instability process of the Temi landslide under conditions of rainfall and seismic activity. The primary conclusions of this study are as follows: (1) While both rainfall and seismic events can lead to landslide instability, earthquakes are the predominant trigger for river-blocking landslides. (2) The Temi landslide event and subsequent damming of the Jinsha River occurred through five stages: seismic-induced rock mass loosening; rear tension cracking and front shear failure; high-speed sliding; front portion crossing the riverbed and climbing the opposite bank; and finally debris accumulation forming the dam. (3) Energy transformation and dissipation are pivotal in landslide dynamics, with frictional heat being the primary energy dissipation source. (4) The evolution of kinetic energy demonstrates initial stability, a gradual increase during sliding, and an eventual decrease to zero upon cessation. The findings of this study indicate that earthquakes are relatively likely to trigger large river-blocking landslides, and the discrete element method has significant advantages in simulating complex geological phenomena, providing important insights for landslide prediction and disaster prevention in earthquake-prone areas.</p>