Abstract: The anchored segment of anti-sliding pile is often assumed as the Winkler elastic subgrade beam for internal force calculation. Based on the power series solution, the traditional foundation coefficient m or K method is applied by using the calculation tables. The calculation procedure is complicated and errors can take place easily because of cut off errors of the coefficients in the tables. Finite difference method is a rational method, but needs the iteration and test calculation methods and more segment number. Based on the foundation coefficient m(k) method, this paper derives the counter force loading calculation formula to analyze internal forces of anchored segment. Compared with the finite difference method, the present method has less segment number and does not need the iteration and test calculation method. The method of controlling its calculation precision is proposed. The calculation program of internal forces for a whole pile is designed. An example is given and shows that this proposed method can improve the calculation efficiency of internal forces of anti-sliding pile and its precision effectively. It can advantage the optimization design for the structure of anti-sliding piles.