Abstract: Hydrocarbon resources condition and later stage reservation condition of Mesozoic-Palaeozoic marine strata were studied in the South Yellow Sea Basin. On the basis of this study, basin modeling means was used referring to the study of the predecessors to simulate hydrocarbon expelling history of marine source rocks and calculate the oil and gas resources, and the hydrocarbon resources potential was also evaluated. At the same time, the favorable accumulation area was forecast through the pool-forming conditions study of the two marine petroleum systems of upper structural layer and lower structural layer, and then favorable exploration areas in the South Yellow Sea Basin was pointed out, which provided basis for next exploration. The results showed that in the South Yellow Sea Basin, source rocks of lower structural layer and Qixia, Longtan-Dalong Group of upper structural layer are presumed to be good source rocks, and Qinglong Group of upper layer is presumed to be middle-good source rocks. Total amount of oil and gas resources in marine strata of the South Yellow Sea Basin is 3.537 billion tons, of which, in the vertical, oil and gas resources are mainly from source rocks of the lower structural layer, and in the plane, oil and gas resources are mainly distributed in the southern depression. There are two types of favorable oil and gas exploration area in the marine strata, in which the most favorable area is located in south of the central uplift, southern depression area and north of Wunansha uplift.