A combustor according to the present invention is provided with: a pilot burner (15) disposed along an axis (P); a plurality of premixing burners (16), each of which has a premixing swirler cylinder (19) and a premixing nozzle (20) disposed inside the premixing swirler cylinder (19) and that are disposed about the axis (P) in the circumferential direction so as to surround the periphery of the pilot burner (15); a substrate (23) through which the pilot burner (15) and the premixing swirler cylinders (19) are individually inserted so as to be supported therein; and stagnation eliminating blocks (27) that are provided so as to fill spaces between the premixing swirler cylinders (19) on a surface of the substrate (23) on the downstream side, wherein air film supplying ports (38) that form air films A on surfaces of the stagnation eliminating blocks (27) are formed in the stagnation eliminating blocks (27).