Abstract: Cretaceous condensate gas reservoirs in Yakela condensate gas field are seriously flooded at the middle-late production stages and it is difficult to stabilize the production. To improve the recovery factor and enhance the remaining oil potential of the gas field, in-depth study on the gas reservoirs and detailed stratigraphic correlation are needed to be done. Based on the integrated study of sand body genesis, stratigraphic sequence isochronous correlation and sedimentary facies (microfacies), taking internal structure, cycle superimposition and cycle combination of sedimentary cycles as breakthrough, ultra-micro cycle interfaces are identified, detailed stratigraphic classification and correlation are carried out, the distribution and blocking properties of interlayers are studied and 5 patterns of remaining oil distribution are established to further optimize development layer series through establishing a relationship among core, conventional logging and saturation logging data. The method can solve the problems of diachronism, sandstone to sandstone & shale to shale, and equal thickness split and so on, which is much closer to the actual underground situation and has popularized significance in the development of clastic reservoirs.