Abstract: The Vulnerability Method was applied to evaluate and forecast the water inrush in the 10th coal seam floor in the Ganhe Mine,Huobao Corporation,with aim to control its threat to underground mining.The results show that the probability of water inrush in the 10th coal seam floor from Ordovician limestone aquifer is generally high.First of all,the southeast part of the mine area is the relative safe site.The central-north mine area is the relative vulnerable site.The fault areas in north part and the other part of the mine area are the most vulnerable sites to form water inrush.The hydro geological condition revealed by the drilling engineering is the same as that of the evaluation result and the validity of the evaluation is proved Finally,some countermeasures for controlling the coal seam floor water inrush were proposed.