Interferometry SAR is an emerging earth observation technique，which is especially useful in cartography and surface subsidence survey. This paper describes the method for monitoring the mining activities using the InSAR technique. Both ENVISAT ASAR and JERS1 SAR data were used to generate deformation interferograms，Characteristics of coherence as well as phase patterns on the C band and L band deformation interferograms were comparatively studied，and the feasibility and limitation of using InSAR technology in mining area subsidence monitoring were analyzed. The experimental result shows that both C band and L band can accomplish the monitoring of mining area subsidence，but C band has more restricted conditions for its perpendicular baseline. For the purpose of obtaining a satisfactory outcome in mining area subsidence monitoring by using the InSAR method，the time series of SAR images of every visit period and SAR deformation interferograms should be established.