Abstract: After studying deformation regularity of monitoring points of old powerhouse deformation body in Shawan hydropower station, it can be concluded that the deformation body features as an integral creep slide, which shows pushing in backyard part and traction in its local frontier part. According to the change in displacement rate, the time-accumulation displacement curve was divided into three sections apparently, and it is presented that the deformation body is stable creeping slowly with a constant deformation rate before August 10, accelerating creep in raising speed with a increasing deformation displacement between August 10 and late September, and deceleration creeping with a slow down deformation rate after October and converging and gradually trending stable in November. After studying the displacement regularity of each monitoring point, it can be reached that the deformable body is induced by unmerited drainage from lock chamber traffic tunnel, rainfall makes an important promotion, and the excavation of new provincial highway has crucial effect on local deformation in deformable body.