As it was of serious geological disasters, the geological disaster prevention and control work in Zhenjiang were carried out earlier and accumulated a certain amount of control management experience. Plastic anchor method was initially put into use in Zhenjiang in the fields of treating perilous rock collapse, and through polar stereographic projection at Chek Lap-analysis on the principles of slope stability analysis, the authors calculated the rocky slope stability with related analysis software, and carried stability comparison before and after treatment, solving the technological problems in harnessing the perilous rock collapse in Xiangshan.