14 wells of LD oilfield are designed to drill into the Liaoxi No.1 fault at depth ranging from 847 to 993 m. This fault is an inherited growth normal fault with a general northeast trending direction and extends through the seabed. To address the feasibility of encountering faults during drilling and the safety of drilling through faults, the sealing performance of the Liaoxi No.1 fault was evaluated using methods such a mudstone smearing factor and cross-sectional normal pressure analysis in conjunction with actual drilling conditions. Through analysis and research, innovative methods have been proposed for calculating the mud weight design for drilling through fault planes and optimizing the trajectory of wells crossing faults, based on the calculated collapse pressure. At the same time, the trajectory of the wells was optimized based on these results. Techniques for preventing and plugging leaks in drilling fluids during fault crossing were also established. The research results provide guidance for the feasibility analysis of drilling faults, wellbore trajectory design, and safe drilling through faults.