Abstract: As a core value of Jiuzhaigou, a UNESCO World Natural Heritage Site, the lake landscape has been significantly affected by the "8·8" Jiuzhaigou Earthquake on August 8, 2017, and its subsequent secondary disasters, with typical water bodies exhibiting clear signs of paludification. To investigate the patterns of post-earthquake surface deformation and changes in lake area, the SBAS-InSAR technique and the SDWI-decision tree method were applied to extract post-earthquake long-term surface deformation data and lake boundaries. The spatiotemporal characteristics and relationships between deformation and lake area were then analyzed. The results indicate that the surface deformation rate in Jiuzhaigou exhibited a staged attenuation pattern, from strong to weak, with the deformation area transitioning from a widespread distribution to localized concentration. Lake area changes were characterized by the coexistence of abrupt post-earthquake expansion and long-term seasonal fluctuations, with notable differences in the fluctuation intensity of lake areas among the three sub-watersheds in the core scenic area. The area of the severely damaged Panda Lake showed a negative correlation with the cumulative deformation in the corresponding small watershed. The study suggests that the post-earthquake lake evolution in Jiuzhaigou is jointly controlled by slope reorganization, hydrological regulation, and sediment-source migration. These findings provide scientific support for understanding the mechanisms of post-earthquake loose-material transport and lake evolution in alpine canyon regions.