Abstract:Kulongshan structure is the most important oil-controlled structure of foreland thrust belt in southern margin of Jiuquan basin, in which the Qingxi Oilfield with ten million-ton-rank of reserve has been discovered.Taking the theory of fault-related folds and thrust structure as a guide and using seismic, drilling, logging and outcrops data to reasonably build up the structural mode of Kulongshan structure, which determined the total structural configuration, the paper points out that the Kulongshan structure is complete and large-scaled fault-turned anticline structure with NW direction on the whole and is cut to five fault blocks with NE direction by many developed adjustment faults with NNE direction, Long-107, Long-11, Long-8-Long-7, Long-15 and Long-14.The oil/gas exploration shows that since differences in formation and petrofacies(lithology), and especially in fracture-developing degree, the different fault blocks have different oil/gas-rich degree.Comprehensive appreciation knows that the Long-15 block among 5 blocks is perspective target in next oil/gas exploration, and the deep of Kulongshan structure has also the better exploration potential.