The seepage at bored concrete pile head has influence to pile concrete stress and foundation bottom waterproof, even leads to corrosion of the reinforcing steel in concrete structure. Combined with the engineering case, the analysis was made to find the main causes of pile head seepage: lack of operation experience and responsibility, unqualified grouting tools, improper concrete quality indexes, too fast pipe drawing at grouting completion, inaccurate measurement of the exceeding height for grouting standard, high water content of foundation soil, high water pressure and etc. with treatment measures of part digging out or blockage by grouting being put forward. The paper introduces the prevention measures including personnel training, apparatus examination, concrete quality control, grouting finishing condition inspection and foundation pit dewatering.