Dayuandu second-line ship lock is adjacent to the structure of the existed junction.Since the geologic condition is complicated and there is a stronger aquifer in the soil layer,problems such as leakage of the dam foundation and abutment possibly occurs,thus the design and construction are difficult technically.Probing into the design idea and construction quality control of the anti-seepage system,we propose to analyze the anti-seepage system from the two angles including plane sealing and section sealing,and take feasible measures on the lap part of high-pressure spraying and curtain grouting.After completion of the construction,both the water pressure test and core sampling test prove to meet the specifications.The anti-seepage measures and inspection methods of high-pressure spraying and curtain grouting used in this project may serve as reference for similar projects.