Abstract: The buried hill fracture system in the middle of Liaohe basin is mainly affected by Mesozoic left transtensional activities.The new generation strong stretching role has the modification of the superposition effect on cracks,and it is good for improving fracture reservoir performance.Core slice identification show that the lithology of buried hill is mainly of mixed granite,with regular buried hill fracture development,good connectivity and wide open degree.The fracture dip is more at 60° ~ 85°,mainly of high angles and good hydrocarbon shows.Oil and gas accumulation research suggests that small depression buried hill is near source sub-sag,with adequate oil and gas supply.There is fault migration,the unconformity surface migration at the top,migration of internal cracks,other oil and gas migration channel and multiple sets of reservoir system.And therefore,it has great potential for hydrocarbon accumulation.