Abstract: Aiming at the effective detection of low signal-to-noise ratio (SNR) point target and the analysis capabilities in clutter background, a template matching filtering method is proposed. The algorithm uses dynamic threshold processing of background gray values, suppresses the background adaptively. When the background is complex, the template matching filtering method for target detection is used to remove the large areas of residual clutter after background suppression, and the extraction of weak target is achieved. The experiment results show that the SNR can be better than 4 dB when the scene is complex，and the detection probability of point targets is increased.