To ensure the ability of retaining water and anti-seepage of earth-rock cofferdam and the construction quality and safety of the project，we adopt the high-pressure rotary jet grouting anti-seepage slab wall in the first section of the earth-rock cofferdam of Qianwei navigation-power junction project in the Minjiang River. According to the research，test and analysis on the construction technology of the double pipe method of the high-pressure jet grouting pile anti-seepage sheet wall，we determine the construction technology and optimal construction parameters. Furthermore，we analyze the advantages of the high-pressure jet grouting pile anti-seepage construction in the earth-rock cofferdam to provide reference for similar projects.