The invention discloses an assembled telescopic buttress universally used in a ring-lock type ladder, and belongs to the field of bridge pier body ladder buttress construction. The assembled telescopic buttress comprises a plurality of fixing frames which surround a ladder and is detachably fixed with the ladder, and a plurality of telescopic systems which are detachably connected with the fixingframes and a pier body. The telescopic system includes wall-attached cross bars detachably fixed with the pier body, and a plurality of groups of telescopic wall-attached slanting bars which are detachably connected with the wall-attached cross bars and the fixing frames. Each group of wall-attached slanting bars is formed by two telescopic wall-attached slanting bars which relatively form an included angle and are connected with the wall-attached cross bar to form a triangular structure. Two ends of the wall-attached slanting bars are respectively hinged with the wall-attached cross bar and the fixing frame. The wall-attached slanting bar is formed by connecting two straight bars. The straight bar is provided with a plurality of bolt holes along a length direction. A bolt passes through the corresponding bolt holes on two straight bars, to detachably fix the two straight bars. The assembled telescopic buttress enhances high pier construction, and makes personnel climb a ladder safely,and the assembled telescopic buttress is convenient in installation, material waste is reduced, and circulation utilization rate is high.