Abstract: Frequency modulated continuous wave synthetic aperture radar (FMCW SAR) has smaller cubage, lighter weight ,lower cost ,higher resolution, etc. Firstly the characteristics of FMCW SAR echoes are discussed and the signal model of multi-channel moving target of FMCW SAR is established in this paper. Then the application of STAP for multi-channel FMCW SAR in GMTI is analyzed. Finally the performance of the method is demonstrated by the simulation.