Abstract: In this paper, the reverberation loss is considered as a basic physical quantity to describe the shallow-water reverberation, and reverberation loss versus time was calculated by using three models:the ray-based model, the WKBZ mode models taking and not taking the effects of complex eigenvalues into account. Numerical simulations show that the effects of complex eigenvalues can not be neglected, and at medium ranges the reverberation loss from the ray-based model is consistent with that from the WKBZ mode model taking the effects of complex eigenvalues into account. The experimental results show that the reverberation loss la not dependent on the bandwidth. The reverberation in shallow water with a thermocline shows strong depth dependence, and the theoretical geometric-mean rule of reverberation intensity was demonstrated by experiment.