An underwater acoustic structure with metal perforated plate inserted into the traditional anechoic coating is proposed to improve the pressure resistance and sound absorption performance of the structure. The deformation of the acoustic structure under different hydrostatic pressure is studied by the static method. By establishing the acoustic finite element equation under the action of hydrostatic pressure, the sound absorption effect of the acoustic structure under different hydrostatic pressure is analyzed. Compared with the traditional anechoic coating, under the hydrostatic pressure of 0 MPa to 6 MPa, the acoustic structure achieves better broadband sound absorption in the mid-to-high frequency range. In addition, the effects of the thickness, material and porosity of the metal perforated plate on the sound absorption performance of the acoustic structure are also discussed. The research shows that the underwater anechoic coating with metal perforated plate is an effective design to improve the pressure resistance and sound absorption performance of underwater acoustic structure.