Abstract: The mining of No. 3 coal seam in Dahebian Coal Mine causes overburden movement deformation and failure，and aquifer water seeps into 130101 working face，which not only seriously damages the ecological environment of the mining area，but also threatens the safety production of the mine.In order to protect water resources，and improve the recovery rate of coal resources，and ensure the safety of mine production，it is necessary to further study the development height and distribution pattern of water-conducting fractured zone in overlying strata. In this paper，the distribution pattern and maximum height of waterconducting fractured zone are given by applying the research method of combining traditional empirical calculation formula and numerical simulation calculation.Finally，the feasibility of the method is verified by the practical measurement method. The method has important scientific significance and application value for protecting the ecological environment of the mining area.

Key words: water flowing fracture, numerical simulation, thin and medium thick, stress distribution, waterproof coal（rock）column