Proceeding of the Joint International Symposium on Deformatuon Monitoring. 2-4 November, 2011. Hong Kong. China. Report. Shanghai maglev is a very fast traffic tool, so it is very strict with the stability of the roadbed. However, the ground subsidence is a problem in Shanhai because of the poor geological condition and some human-induced factors. So it is necessary to monitor ground subsidence in the area along the Shanghai maglev precisely and frequently. Traditionally, precise levelling method is used to survey along the track. It is expensive and time consuming, and can only get the ground subsidence information on sparse benchmarks. Recently, small baseline differential SAR technique comes into playing a valuable part in monitoring of ground subsidence, which can extract ground subsidence information in a wide area and with high spatial resolution. In this paper, L-band ALOS PALSAR data and C-band ENVISAT ASAR data are used to extract ground subsidence information using SBAS method in Shanghai maglev area. The results show that the general pattern of ground subsidence from InSAR processing of two differential bands of SAR images is similar. Both results show that there is no significant ground subsidence on the maglev line. Near the railway line, there are a few places with significant local subsidence rates at about -20mm/y or even more, such as Chuansha town, the junction of the maglev and Waihuan road.