China National Offshore Oil Co., Ltd. (CNOOC)'s natural gas production-supply-storage-marketing system in the region north of the Yangtze River is in its initial stage of construction. In order to speed up its construction, CNOOC established a natural gas production-supply-storage-marketing system with CNOOC's characteristics based on the current situation of CNOOC's production-supply-storage-marketing system in this region according to national construction ideas of production-supply-storage-marketing system. This system has the following characteristics. First, the layout framework is supported by seven pillars with CNOOC's typical characteristics, and the quantitative analysis structure is composed of 14 elements, which can systematically evaluate enterprises' overall adaptability to construct the natural gas production-supply-storage-marketing system and effectively identify redundancy degree or "bottleneck" of specific facilities one by one. Second, this system takes the limited expected market target as the orientation, the construction of gas storage facilities as the breakthrough point, the regional "self-balance" as the core of the system, and the "resource-facility-market" balance with a certain amount of margin as the construction principle. And the following conclusions were obtained. First, large-scale mutually supporting annual natural gas turn over, vaporization transportation, gas storage and peak shaving capacity can be built in the region north of the Yangtze River through unified coordination of "offshore gas + LNG" resources and the natural gas infrastructure layout of "four points, N stations, one network". Second, based on the integrated allocation of "resource pool" and the hour-level peak shaving capacity of LNG receiving terminals, the large-fluctuation gas demand can be guaranteed with high-elasticity gas supply. Third, the surplus capacity of the production-supply-storage-marketing system in the coastal areas south of the Yangtze River can reach directly or commercially exchanged to the areas north of the Yangtze River. And the flexible distribution of offshore LNG resources and the allocation of onshore transported pipeline gas in the transportation direction provide support and mutual guarantee in a larger range for the construction of the production-supply-storage-marketing system in the region north of the Yangtze River.