Abstract: The problem of further use for goaf involves in more factors, It is a very difficult subject. Proved by theoretical analysis and practice research, it is obtained that numerical simulation has advantages such as accurate and visual for the solve of goaf problem. The article concludes and analyzes the commonly used numerical simulation method and makes further analysis on their respective principles and applicability. Combined with FLAC^3D software, mining foundation water-rock coupled problem is anlyzed as an example.