Abstract: Owing to the fine resolution of TerraSAR-X data provided since 2007,this paper applied 6 TerraSAR data(strip mode) during 3rd Dec.2009 to 23rd Mar.2010 to detect and monitor the active fissures over Xi'an region.Three themes have been designed for high precision detection and monitoring of Xi'an-Chang'an fissures,as small baseline subsets(SBAS) to test the atmospheric effects of differential interferograms pair stepwise,2-pass differential interferogram with very short baseline perpendicular to generate the whole deformation map with 44 days interval,and finally,corner reflector(CR) technique was used to closely monitor the relative deformation time series between two CRs settled crossing two ground fissures.Results showed that TerraSAR data are a good choice for small-scale ground fissures detection and monitoring,while special considerations should be taken for their great temporal and baseline decorrelation.Secondly,ground fissures in Xi'an were mostly detected at the joint section of stable and deformable regions.Lastly,CR-InSAR had potential ability to monitor relative deformation crossing fissures with millimeter precision.