Abstract: The lithologic reservoir is characterized by small scaled sand bodies, strong heterogeneity and complex oil-water distribution, which results in the complicated connection between reservoir sand bodies and unclear distribution regularity of sand bodies. Based on the single reservoir correlation method with "Cyclic Correlation, Grading Control, Different facies zones are differently treated" is used to determine the connectivity of sand bodies between wells. "Correct, Disassembly, Series and Verification", the four-step method was used to improve the accuracy of sand body connectivity research in Dainan formation of Huangjue oilfield in Gaoyou sag and provide a geological basis for the adjustment of injection-production series and streamline field in lithologic reservoirs.