Abstract: To improve the performance of active sonar detection in polar ice-covered regions, the attenuation characteristics of the average bistatic reverberation intensity under Arctic ice cover are investigated. The ice layer is first modeled as an elastic medium with a rough lower interface, and the coherent reflection coefficient and scattering intensity of the seawater-elastic ice layer rough interface are numerically calculated. The seabed scattering characteristics are described by an empirical scattering function. The bistatic scattering region of the underwater reverberation is determined using the elliptical ring partitioning method, leading to the establishment of a bistatic marine reverberation model under the ice layer. The results show that the scattering intensity beneath the ice is significantly higher than the surface scattering intensity within the grazing angle range of 0°−70° at an average wind speed of 5 m/s. The ice layer parameters and the transmitted signal frequency mainly affect the scattering intensity beneath the ice, thereby causing variations in the underwater reverberation intensity. Among these, the shear wavespeed, ice layer thickness, root-mean-square roughness height of the lower ice interface, and incident sound wave frequency have the greatest influence on the underwater reverberation intensity and attenuation trend. As the root-mean-square roughness height of the lower ice interface and the incident sound wave frequency increase, the reflection loss beneath the ice increases, and the seabed reverberation intensity decays more rapidly with time. Finally, the effectiveness of the model is validated using reverberation data from an Arctic air-gun source.