To solve the problem of low recognition rate of interrupted-sampling and repeater jamming， a method of jamming recognition based on short-time fractional Fourier transform（STFRFT） was proposed. In order to reduce the complexity of feature extraction in time-frequency domain， the time-frequency domain was reduced to fractional Fourier transform（FRFT） domain and time domain based on maximum search and slice after STFRFT was used to interrupted-sampling and repeater jamming. Feature parameters contained the number of spectrum peaks in FRFT domain， and the number of pulses in time domain after dimensionality reduction. For three typical kinds of interrupted-sampling and repeater jamming， simulation result shows that a satisfactory recognition effect is achieved when the jamming-to-noise ratio is greater than -4 dB.