Abstract: This paper makes numerical modeling of seismic wave field in the advanced detection surveillance system that the shotpoint is away from the coal face by applying staggered grid finite difference method, and seismic wave field characteristics of various wave patterns in different models are analyzed. As a result, the interference wave in the roof can be eliminated effectively when the shotpoint is on the floor; reflected waves of geological interface are clear and show negative apparent velocity, so it can be recognized and extracted by using apparent velocity wave filtering; the diffraction wave of coal face is the main interface wave, the diffraction wave train is wider than other waves and it is predictable.