Abstract: In this paper two major methods of simulation of sound fields are commented on: Monte Carlo method and ray-tracing technique; Then the investigation into the infleunce of the geometry of rooms, the distribution of absorbers and the absorption coefficient itself on the reverberation in a room is simulated and discussed by use of the method developed in this paper; finally, as an example the reverberation time and the directional distribution of early reflected sound energy between 0-80 ms are calculated, demonstrating the utility of computer simulation in room acoustics.