Abstract: Interrupted sampling repeater jamming based on digital radio frequency memory (DRFM) can form a large number of false targets that combines the effect of both suppression jamming and deception jamming, which is difficult to be accurately detected and identified by traditional methods. A novel jamming identification method based on short-time fractional Fourier transform (STFRFT) is proposed in this paper for two typical interrupted sampling repeater jamming: chopping and interleaving (C&I) jamming, and smeared spectrum (SMSP) jamming. Firstly, the optimal rotation angle of the fractional Fourier transform of the jamming signal is selected by traversing each angle. Then STFRFT is performed to obtain the time-frequency distribution image of the received signal. The jamming parameters are extracted by using image binarization method to identify the jamming. The simulation results verify the effectiveness and accuracy of the proposed method.