Digital Elevation Models (DEMs) are used in many applications in the context of earth sciences such as in topographic mapping, environmental modeling, rainfall-runoff studies, landslide hazard zonation, seismic source modeling, etc. Accurate DEM can be derived from SAR (Synthetic Aperture Radar) acquisitions by InSAR (Interferometric synthetic aperture radar) technique which has advantages over other methods for the generation of large area DEM. However, the processing of InSAR data is still a challenging task. This paper reviews InSAR operational steps and processing chain for DEM generation from Single Look Complex (SLC) SAR data of ERS-2 and compare a IJRDO-Journal Of Electrical And Electronics Engineering Volume-2 | Issue-8 | August,2016 | Paper-5 22 satellite SAR estimate of surface elevation with existing ground control points (GCPs) in the study area. The preliminary results of this comparison range from about 2 to 10 meters overall the area of the used InSAR products with a standard deviation range between ±0.40 m to ±1.74 m.