Abstract: In order to obtain better frequency aiming jamming effects, it is necessary to design a band-pass filter with a pass-band as narrow as possible and the attenuation outside the pass-band as large as possible, so as to avoid the effect of the transmitting jamming signal leakage on the normal signal reception. Due to limited existing hardware resources and that the existing design method of filter transition band and out-of-band attenuation cannot meet the design requirements of high-performance filters, in this paper, an improved structure designed by the two-stage interpolated finite impulse response-frequency response masking (IFIR-FRM) filtering technique is used for the high-performance band-pass filter to meet the performance requirements of the underwater acoustic countermeasure equipment, while reducing design complexity. The simulation results show that this method is quite effective in reducing the computational complexity of narrow band-pass FRM filter, the order of the target filter and the use of the multiplier units. The required technical indicators of the frequency aiming jamming mode can be achieved.