Based on 26 scenes of Sentinel 1 ascending data from October 22, 2014, to April 11, 2019, the deformation monitoring test of the Jiyunhe fault, a buried fault, was carried out using the PS InSAR technology. Results show the following:(1)The Ninghe area in the south of the study area is strongly disturbed by land subsidence, which leads to gradual weakening toward the north and basically disappears in the north of the northern segment of the Jiyunhe fault.(2)The deformation rate of the northern part of the study area in the direction of the line of sight(LOS)is about 0 mm/a in the northern segment of the Jiyunhe fault and increases northward with the distance from the fault, indicating that the northern part of the study area controlled by the nearly EW trending Yanshan uplift has a trend of tilting toward the south.(3)The movement mode in the northern segment of Jiyunhe fault is stick slip. The difference in LOS relative deformation rate between the two sides is about 1.83 mm·a-1,while that between the two sides of the southern segment of the Jiyunhe fault is less than 2.96 mm·a-1,which is close to the leveling results from 2005 to 2012, indicating that since 2005, the Jiyunhe fault has been relatively stable.(4) Under the influence of land subsidence, the InSAR deformation field of buried fault contains a lot of non structural information, so the specific deformation rate of a fault cannot be obtained. However, the aquifers on the two sides of the fault have different thicknesses due to the fault activity. The land subsidence amplitude caused by groundwater overdraft is also different. Correspondingly, the InSAR deformation field changes abruptly on the two sides of the fault, which is of certain significance in determining the location of hidden faults.