Abstract: The Tange ancient landslide, located in the upper Jinsha River on the southeastern Tibetan Plateau, is a large landslide with complex spatial structure features and strong deformation. However, a comprehensive study on the developmental and deformation characteristics of the Tange ancient landslide is lacking. In this study, remote sensing interpretation, InSAR, UVA, and field survey techniques were employed to analyze and investigate the deformation characteristics and influencing factors of the Tange ancient landslide. By applying SBAS-InSAR method to the 144-view Sentinel-1 uplift data from January 2016 to February 2022. The maximum deformation rate reached-87.2 mm·a^-1 in the line of sight(LOS)direction of the radar, with a cumulative deformation of up to 590 mm. Based on the InSAR deformation monitoring results, the deformation zone of the Tange ancient landslide was classified into four categories: very strong deformation zone(V_LOS < -70 mm·a^-1), strong deformation zone(-70 mm·a^-1≤V_LOS < -44.2 mm·a^-1), weak deformation zone(-44.2 mm·a^-1≤V_LOS < -18.4 mm·a^-1), and stable zone(V_LOS≥-18.4 mm·a^-1), a significant deformation zone was identified in the middle and front part of the Tange ancient landslide, exhibiting high creep deformation. Field surveys confirmed the deformation monitoring results of SBAS-InSAR, revealing surface deformation phenomena such as scraps, retaining wall deformation, and highway cutting slope in the strongly deformed area of the Tange ancient landslide. The deformation of the Tange ancient landslide is significantly influenced by heavy rainfall and exhibits a high-level creep deformation mode. The effect of heavy rainfall shows a lag in time, characterized by intermittent creep stages such as stationary creep, slow creep, and accelerated creep. The study concludes that the Tange ancient landslide is prone to destabilization under the influence of heavy rainfall, leading to a landslide-mudslide hazard chain with a potential risk of blocking the Jinsha River. It is recommended to enhance remote sensing investigation, InSAR deformation monitoring, and risk prevention research on creep deformation landslides in the Jinsha River Basin.