Abstract:  Due to the rapid development of digital radio frequency memory，transmitted deceptive jamming become a big threat to affect the precision tracking radar. To suppress the deceptive jamming, an anti jamming algorithm based on Stretch processing with CPI echo is proposed. The delay and Doppler frequency of the current CPI are estimated using the distance and speed from the last coherent processing interval. Target signal and jamming signal are separated by using the Stretch processing between constructed baseband echo and the current CPI signal. After filtering the high frequency interference, the signal only contains target for moving target detection and constant false alarm detector. Simulation results show that the proposed anti-jamming algorithm can restrain the interference effectively in the situation of single false targets jamming or dense deceptive jamming. Furthermore, the algorithm can still be applied in the condition of flexible target, multi-scattering center target and multi-target tracking.