In order to improve the detection performance of underwater acoustic transducers, a new method for calculating broadband impedance matching network and attenuation of residual interference signal is proposed. First, the Krimholtz, Leedom, and Matthaei (KLM) model of the underwater acoustic transducer is derived, and then, the circuit network is constructed by combining it with a T-type impedance matching network, and the port impedance function is obtained. Based on the impedance function, multiple computational boundary conditions are constructed based on the impedance of the center frequency and the frequencies on both sides of the frequency band, and the maximum difference of the matched impedance in the frequency band is limited to obtain a relatively flat power response. Compared with the traditional resistor-residual vibration attenuation method, the current detection attenuation method proposed in this article has a higher truncation efficiency of the residual vibration signal. The experimental test shows that compared with the Smith diagram impedance matching design method, the proposed impedance matching network has better broadband characteristics. It can increase the active power by 600%, widen the bandwidth by 200%, and the maximum power in the frequency band is less than 20 W. The residual vibration attenuation method of current detection can effectively attenuate 75% residual vibration signal without loss of the original waveform.