Most of the underground gas storage reservoirs built in China are converted from gas reservoirs. Nanbu N Reservoir is the first offshore oil and gas reservoir-type gas storage reservoir in China, with oil-ring gas reservoirs and gas-topped oil reservoirs developed in the reservoir area. Unlike gas reservoirs, oil and gas reservoirs are built with oil, gas and water three-phase fluids interacting with each other, and the seepage mechanism is complicated. In order to improve the degree of inventory utilization and realize the efficient operation of the reservoir at capacity and capacity, we have carried out the exploration of the technology of this type of reservoir to improve the utilization of the inventory. The research results show that: ① the fluid distribution in water-flooded reservoirs is complicated, and the main factors affecting the degree of inventory utilization are reservoir non-homogeneity, injection and drainage methods, pressure difference, well network distance, and underground water storage; ② the use of zoned differential injection and extraction and sequential injection and extraction by wells on the regional level can realize balanced injection and extraction; ③ for gas reservoirs with oil rings, the use of top horizontal wells to strengthen the injection of gas, and the slow injection of gas into the straight wells at the waist can realize the injection of gas to fill the gas roof area quickly and gradually expand and diffuse to the gas roof area, and then gradually expand and diffuse to the gas roof area, and gradually expand and diffuse into the gas reservoir. The gas top area can be filled quickly and gradually expanded and diffused to the oil area, which improves the drainage efficiency of the oil area and improves the utilization rate of the stock. ④For gas-top reservoirs, one-way gas drive is adopted at the initial stage, and high-pressure area drive is used to discharge liquid plus step-by-step pressure boosting and expansion at the later stage, and the full-time rate of liquid discharge is matched with the adjustment of flow field to improve the degree of utilization. ⑤ Optimized injection and extraction structure, integrated above and below ground, realized differentiated and refined gas injection in gas reservoirs, and improved the efficiency of gas drive capacity expansion. Mining practice shows that since the application of this technology for three years, the degree of utilization has been increased by 9.5%, which effectively guides the efficient operation of oil and gas reservoir-type gas storage, and can provide reference for the analysis and utilization of the inventory of similar gas storage reservoirs.