NOVELTY - The combined type ecological purifying cage comprises an outer frame and a biological filler set in the outer frame. An inner wall of the outer frame is provided with a stuffing bracket. The biological filler is fixed on a supporting bracket. The outer frame is further provided with a connecting piece. The supporting bracket comprises a ring frame, a fixed rod and a supporting rod. The supporting rod is provided with multiple supporting rods. The fixed rod is fixed on the supporting rod. An outer side wall of the bottom frame is provided with an aeration pipe.    USE - The combined type ecological purifying cage is useful for processing and recycling domestic sewage and industrial waste water, landscape water and river water.    ADVANTAGE - The combined type ecological purifying cage has good water quality and small floor area, and is inexpensive.    DETAILED DESCRIPTION - The combined type ecological purifying cage comprises an outer frame and a biological filler set in the outer frame. An inner wall of the outer frame is provided with a stuffing bracket. The biological filler is fixed on a supporting bracket. The outer frame is further provided with a connecting piece. The supporting bracket comprises a ring frame, a fixed rod and a supporting rod. The supporting rod is provided with multiple supporting rods. The fixed rod is fixed on the supporting rod. An outer side wall of the bottom frame is provided with an aeration pipe. The connecting piece is matched and connected with a connecting ring by a bolt. An outer section of the frame is round, oval or polygon. The purifying cage further comprises a protector. The protector is arranged with front side of the purifying cage unit body, and comprises a shell, a water inlet, an overflow pipe, a grid and an oil-water separating plate. The grid water inlet is set on a back side of the oil-water separating plate. The oil-water separating plate is provided in a back side of the grid. The overflow pipe is set on an upper part of the shell. The grid is a metal screen. A vertical section of the oil water separating plate is wave-shaped or plane-shaped.