Abstract: The change of external load of slide-resistant piles under influence of prestress is not clear at present. To further investigate the problem, soil pressure and anchorage force of stabilizing piles with prestressd anchor cable were monitored for a long time, with Nanshan landslide treatment in Xinmin No.2 mine, Liliu Coking Coal Group, Shanxi as the research object. Then the distribution and the changes of soil pressure, and the prestressing losses of anchor cable were analyzed, based on which the effect of prestress action on soil pressure acting on the back of the piles beyond the sliding surface was analyzed. The result shows that in the stage of prestress aplication, the effect of prestress action on soil pressure acting on the back of the pile beyond the sliding surface was mainly related to the initial prestress and the structure of slide-resistant pile. In the stage of driving force action, the main performance of the effect of prestress was the impact of the distribution of landslide thrust. Under the long-term effect of prestressed anchor cable, the distribution of driving force tends to be more uniform.