Abstract: In the gas storage in Changqing area, during the process when drilling horizontal wells with large-scale boreholes in the fourth section, in view of the fact that it is difficult to carry sand in large boreholes, the rate of penetration is low, it is difficult to control well trajectory, the well wall is unstable and collapsible, the contradiction of collapse and leakage is prominent, downhole failures occur frequently, and cementing requires high qualities, by analyzing the formation characteristics and engineering difficulties encountered during drilling, and based on the technique researches on such as wellbore wall stability, wellbore structure optimization in terms of improving rate of penetration, wellbore trajectory control, drilling fluids with strong plugging and strong inhibition, well cementation, and well completion, the key technologies for horizontal well drilling and completion in gas storage were formed. The key technologies include: conduit+four-section slim hole well structure, well trajectory control technology, water-based drilling fluid system of strong plugging and strong inhibition, and screen+liner half-process cementing and completion supporting technology. These technologies were applied to 2 wells in the Shan 224 gas storage area, with an average drilling cycle of 120.25 days and an average rate of penetration of 5.24 m/h, and the qualified rate of wellbore quality was 100%. Compared with the well completed before optimization, the drilling period was shortened by 49.79%, the rate of penetration was increased by 174.74%. This technology provides a technical support for efficient, high-quality, and rapid drilling of horizontal wells in the gas storage of Changqing Oilfield in the Ordos Basin.