Abstract: There are two sets of hydrocarbon accumulation systems in Southern Anhui namely, Triassic Yinkeng Formation and Permian Dalong Formation-Longtan Formation. However, this region has developed complex structures and faults, and the soft and hard formations were interlaced with frequent changes. Various complex situ-ations such as reduced diameter, lost circulation, wall collapse and stuck drill often occurred, and there is a high-pressure gas layer locally, which has caused huge challenges during drilling construction. By adopting the technical measures of plugging while drilling, composite plugging, special shale-coring bit, hybrid bit and strong inhibitory drilling fluid, the optimal and fast drilling has been realized in Well Wanjingdi 2, so the drilling cycle has been shortened by 24 days. Besides, the elastic and ductile double condensation and double density cementing technology was used to guarantee the cementing quality of production casing, which provides technical guarantee for the next stage of fracturing and gas testing. This technical system can provie some valuable references for similar drilling projects in the future.