Abstract: Based on the characteristic analysis of hyperbolic frequency modulated(HFM) signal,a new kind of detector towards HFM signal was put forward,which was called Variance-of-Period-Slope Detector,VPSD for short.According to the probability density of the variance-of-period-slope in different SNR,the detector's binary hypothesis testing mode was indicated,and then the property of VPSD and that of matching filter(MF) were compared in the same condition.The simulation result shows that VPSD is a kind of constant false alarm rate detector,which can detect HFM signal effectively in low SNR,and can adapt to the Doppler mismatch very well.