The Paleogene sedimentary thickness in the Sanmenxia Basin in Southern North China is large and continuously distributed， with developed dark mudstone. Through the deployment of drilling projects， new discoveries of oil and gas in small and medium-sized basins can be assisted. However， the geological environment for drilling in this type of reservoir is complex， with frequent sand and mudstone interlayers， which can easily cause engineering difficulties such as bit mud entrapment， wellbore collapse， block falling， coexisting risks of leakage， and difficulty in drilling. Through the optimization of drilling tool combination and wellbore structure， research on drilling fluid technology in different sections， development of PDC irregular tooth drill bits， and research on the drilling process of “low speed + medium drilling pressure + screw + high-efficiency PDC drill bits”， effectively solved the problems of wellbore stability and drill bit selection. In the actual drilling of Well YXD1， the average mechanical drilling speed of comprehensive drilling reached 5.67m/h， that improved 30%， which shortened the drilling cycle by 10 days compared to the design. Innovations have formed a “new， superior， and fast” drilling and completion technology system for sand and mudstone interlayers in the Sanmenxia Basin， including a mud pack drilling fluid technology system， a long open hole wellbore protection drilling fluid technology system， an efficient PDC shaped cutter drill bit acceleration technology for sand and mudstone interlayers， and a “two low and one high” variable density cement slurry cementing technology that can be promoted. This can provide useful reference for drilling engineering design and construction in similar regions.