PROBLEM TO BE SOLVED: To improve combustion efficiency of a gas burner, to stabilize combustion and to make combustion temperature characteristics of a material to be burned at an initial stage of combustion suitable for the kind of the material to be burned in a tunnel type oven.SOLUTION: A tunnel type oven includes a plurality of convection heaters having suction ports arranged at the outside of a combustion furnace, suction pipes that make the suction ports communicate with a combustion room and take air outside the furnace in the combustion room, air jetting tubes that are connected to the suction pipes and have small holes for jetting air outside the furnace toward the material to be burned, pressure detection parts arranged on the suction pipes and pressure blowers for regulating pressure in the suction pipes at the entrance zone of the combustion room. The tunnel type oven further has a convection heater control part equipped with a memory part of a pressure value in a standard suction pipe for memorizing the pressure value in the standard suction pipe fit for the combustion condition of the material to be burned and a pressure blower control part for controlling the actuation of the pressure blower based on pressure values detected by the pressure detection parts and the memorized pressure value in the standard suction pipe.
