PROBLEM TO BE SOLVED: To provide a tunnel kiln capable of elongating a life of refractory lining and is easily maintained even when tar is produced in a furnace in a degreasing process of organic components contained in a body to be sintered, and to provide a method of manufacturing a sintered body using the tunnel kiln.SOLUTION: A tunnel kiln includes: a tunnel kiln body having a degreasing zone and a sintering zone, in which the degreasing and sintering of a body to be sintered containing organic components are respectively performed, and having an inner wall comprising the refractory lining; a conveyance means which conveys the body to be sintered toward the outlet side from the inlet side of the tunnel kiln body; and a lining disposed so as to cover at least the inner wall of the degreasing zone on the inner wall of the tunnel kiln body.