Abstract: A compost maker comprising an upright container having on its top end a cover for introducing material to be composted in the container, having in its lower part a hatch for removing composted material from the container, and containing an air tube system for guiding air in among the material to be composted. The air tube system comprises at least two tubes on different heights, the lower tube being connected through the wall of the container with an air intake aperture, and which are interconnected with a connecting tube and their lower parts provided with holes. The cover is fitted with an exit duct, the air flowing through the holes in the tubes and upward through the material to be composted and through the exit duct out from the container. The material to be composted, supported by the transverse tubes, moves in controlled manner downwardly as the composting of the material progresses.