It is necessary to simulate seafloor reverberation time series for testing and evaluation of active sonar signal-processing algorithms and active sonar system-performance models. Traditionally, for an isovelocity sound-speed profile, consider simulating only the reverberation arising from direct-path propagation from the source to a scattering patch on the seafloor and back to a receiver. Actually, the effect of multipath propagation can't be ignored. Therefore, the reverberation model based on multipath propagation theory is proposed, and a method for simulating reverberation time series is presented with the seafloor is divided into range-azimuth cell. The simulation data will be useful in the evaluation of active sonar system.