The invention discloses a multi-stage finned radiator. The multi-stage finned radiator comprises a strip-shaped bottom plate and first-stage fins arranged on the two sides of the bottom plate. The first-stage fins are diverged outwards from the two sides of the bottom plate. Multiple second-stage fins are arranged on each first-stage fin. A heat exchange face is arranged on the outer surface of the bottom plate. A mounting structure is arranged on the outer portion of the bottom plate. By arranging the heat exchange face and protruding strips, heat dissipation is conducted through a combined manner of heat conduction and heat radiation, the heat dissipation area is guaranteed, and heat conduction efficiency is improved, so that the heat dissipation efficiency of the whole radiator is improved, consumption of materials is reduced, and production cost is lowered.