Powerhouse of TALEGHAN water control project of Iran is located in the mountains on the left bank of reservoir area. With high seepage pressure of 80m water head height, the construction was difficult because of extremely high requirements for seepage control on underground powerhouse. On this basis, targeted wet grinding cement grouting was applied in weak permeable layer with good effects. The paper mainly introduces the construction method of enclosed curtain grouting for underground powerhouse, which can be reference to the similar projects.