The invention discloses a band-pass filter with an adjustable narrow-band trapped wave. The band-pass filter comprises a main resonator; a first trapped wave unit and a second trapped wave unit which are symmetrically arranged left and right, an input feeder line and an output feeder line which are symmetrically arranged left and right. The main resonator is used for generating a pass band; the first trapped wave unit and the second trapped wave unit are coupled with the slit of the main resonator respectively, and are used for generating the narrow-band trapped wave in the pass band, and each of the two sides of the first trapped wave unit and the second trapped wave unit is provided with a variable capacitance circuit; the variable capacitance circuit is used for changing the resonance frequency of the first trapped wave unit and the second trapped wave unit to make the narrow-band trapped wave adjustable; the input feeder line and the output feeder line are coupled with the two side slits of the main resonator. The band-pass filter with the adjustable narrow-band trapped wave is applied in a radio frequency transceiver to inhibit a specific frequency band, there is no need to additionally add a trapped wave filter, the size of the radio frequency transceiver is reduced, moreover, the narrow-band trapped wave in the pass band is adjustable, interference signals in different frequency bands are inhibited, and the operation is simple.