Abstract: Synthetic aperture radar differential interferometry (InSAR) has been widely used in ground subsidence monitoring of urban mines due to its characteristics of all-time, all-weather, wide range and high accuracy. However, for landslide disasters in mountainous areas, the monitoring effect of InSAR for landslide disasters is not ideal due to the influence of topography, vegetation coverage and deformation characteristics of disaster bodies. Taking the Fanjiaping ancient landslide (composed of Muyubao landslide in the west and Tanjiahe landslide in the east) in the Three Gorges Reservoir as an example, the deformation time series and deformation rate are calculated by Small-Baseline Subsets (SBAS-InSAR) based on Sentinel-1A radar satellite data. The results are compared with GNSS surface displacement monitoring results in the same period. The results show that the whole Fanjiaping landslide is in a state of peristaltic deformation, in which the deformation of Muyubao landslide is small, and the change of the middle and front of Tanjiahe landslide is obvious. The subsidence trends of the two landslides are similar to GNSS results, with the same order of magnitude, which proves the reliability of InSAR results, and also indicates that SBAS-InSAR technology is suitable for landslide dynamic monitoring.