The differential tensioning method can effectively improve the tensioning efficiency of the prestressed anchor cable with pressure dispersion, which has been successfully applied in the slope reinforcement for the drain building of Lianghekou Hydropower Station. In order to ensure the balanced load of the steel strand when tension reaches 110% of the design load, the differential compensation load is calculated and analyzed, and it is found that the difference generated in the pretightening stage is key to balanced load. The single differential compensation and the overall tension stage are briefly introduced and analyzed.