Abstract: Xinchang gas field is a typical complex gas field in the West Sichuan Depression which has already taken shape and is bearing gas in multiple strata and superimposed by,ulti-type gas pools.Based on the pressure zonation and gas-water occurrence of overpressure gas source in the Xujiahe Formation as well as six types of gas pools established or predicted,the multi-factor comprehensive concept "pool-forming environment" is proposed by fine description of 3-D seismic interpretation results. Furthermore,five types of pool-forming environment with different pool frming mechanism are classified in Xinchang gas field,the pool-forming conditins and,main controlling factors of each pool-forming environment are analysed,and the identification marks of each pool-forming environment are suggested.