Abstract: In view of the floor water inrush problem in the lower coal mining group, Longgu mine field is taken as the research object.After comprehensive analysis, three main control factors include fault, ordovician limestone water pressure and effective water-resisting layer thickness are determined, and the thematic maps of the three main control factors is obtained by Surfer software.Using analytic hierarchy process(AHP) and trapezoidal fuzzy number method(TFN) to calculate the weight of the first order factors and their subclasses respectively, a prediction model based on AHP-TFN model is established.The risk of water inrush from coal floor is divided into different zones, which provides scientific basis for prevention and control of water inrush from coal floor during mining.