Abstract: Gas is the main factor effecting mine safety.This paper presented a general method to establish a model based on Bayes stepwise discriminant analysis to establish and forecast gas geological condition. At the same time, on the base of analyzing the data of Pansan mine in Huain-an, through creating the index system of gas geological condition and splitting the same equality blocks, the gas geological conditions are evaluated and forecasted in the mining area.The results provide important information for coal mining planning and gas controlling.