The invention discloses an open-center biomass gas production furnace. The furnace comprises: a cylindrical inner container, wherein the top of the cylindrical inner container is provided with a material inlet, the bottom of the cylindrical inner container is provided with a first material outlet, and the lower end of the cylindrical inner container is provided with one or more lighting-up tuyeres; an outer cylinder, wherein the outer sleeve is sleeved outside the cylindrical inner container, an annular cavity is formed between the outer cylinder and the cylindrical inner container, and the annular cavity is provided with a gas outlet; and at least two connecting tubes uniformly and symmetrically connected between the upper end of the cylindrical inner container and the annular cavity, wherein the gas outlet, the annular cavity and at least one of the connecting tubes form a gas flow channel connected with the cylindrical inner container. The open-center biomass gas production furnace has the advantages of automatic raw material feeding, continuous production, continuous material discharge, continuous gas production, simple structure and convenient use.