Abstract: By adopting basin simulation technology,the evolution of paleo-fluid potential in the second member of Jialingjiang gas reservior in northeast Sichuan has been studied in this paper.In early-middle Jurassic period,the gas potential is mainly ranged from 55 kJ/kg to 85 kJ/kg,with the average value of 71.776 kJ/kg.When it went to late Jurassic period,the extent of gas potential is 110~155 kJ/kg,with its average key up to129.546 kJ/kg.Now the gas potential is 30~130 kJ/kg,with the average value of 89.114 kJ/kg.The results show that distribution of paleo-fluid potential in the Second Member of Jialingjiang gas reservior is mainly controlled by pressure.Besides that there is a certain inheritance in paleo-fluid potential evolution.It is shown by the study that such low potential regions as Wenquanchang,Tieshan,Leiyinpu,Tieshanpo,Huanglongchang and Tingzipu are the prospect areas of gas accumulation.This study provides geological reference for further exploration of the second member of Jialingjiang gas reservior.