Abstract: The hydrogeological conditions in Xingtai coal mine are analyzed in order to mine the lowest coal seam under safe conditions.The study is focused on the affecting factors and mechanism of water inrush from coal seam floor.The risk analysis for water inrush from Ordovician limestone before mining has been made by using GIS.The mining area is divided into three parts,i.e.safe area,potential water inrush area and water inrush area.Meanwhile the range for initial mining is delineated.