Pile subsidence often occur for cement grouting in secant pile casing, both construction quality and economic effectiveness is affected. Discussion was made on this problem with field cases, which was mainly caused by compression of residual soil and pile-end soil at the bottom end of the pile, and by cement solidification of pile body. According to K1 value of the empirical coefficient, theoretical amount of subsidence could be predicted, which could be taken account by saving the same amount of pile height in design and grouting the same amount more of cement.