The use of synthetic aperture radar satellite images can obtain information on surface deformation and subsidence. Based on multi period radar images of long time series, it can monitor surface deformation at the millimeter level, with the characteristics of wide monitoring range, high accuracy, and fast response speed. This method, combined with optical remote sensing, can synergistically achieve effective support for urban safety. It can periodically conduct safety inspections on urban buildings, bridges, highways, water conservancy facilities, and oil and gas facilities, and can early identify settlement and slope disasters.