Abstract: Interrupted-sampling repeater jamming is a new kind of coherent interference, it can obtain partial pulse compression gain. The jamming can achieve effects of both deception and suppression, which make it a big threaten to modern radar. Fully understanding jamming characteristics is the precondition of achieving jamming recognition and countermeasure. In this paper, jamming model is firstly built and related analytical expression of pulse compression output is derived on the basis of introducing the principle of interrupted-sampling repeater jamming; then, analyzing formation mechanism of jamming false target and the influence of key parameters on the interference characteristics. Finally, the influence of interrupted-sampling repeater jamming on target detection performance under different signals is compared by simulation. Simulation results demonstrate that jamming effect is deceptive for linear frequency modulation signal and it’s suppressible for phase coded signal.