The invention discloses an aeration biological filter-artificial wetland combination sewage low-carbon treatment reactor which comprises an inner-layer circular water distribution region, a middle-layer annular aeration biological filter and an outer-layer annular artificial wetland, wherein the water distribution region is communicated with the middle-layer annular aeration biological filter through a water distribution region overflow port; the aeration biological filter is communicated with a water inlet on the bottom of the outer-layer annular artificial wetland through a water outlet on the bottom of the aeration biological filter; the aeration biological filter is composed of double layers of annular passages; anoxic regions A and aerobic regions C are arranged in the double layers of annular passages in a staggered mode; an interval is kept between two filler frames, and a clearance is kept between the filler frame and the tank wall; and the artificial wetland is formed by sequentially connecting the anoxic regions A, natural reaeration regions B and aerobic regions C. The invention has favorable denitrification effect, thereby reducing the generation of nitrous oxide greenhouse gas; the invention avoids the blockage of the filtering layer of the aeration biological filter, and the aeration biological filter can be easily cleaned; and the sewage treatment effect is good.