An infrared radiation heater includes: a combustion chamber having a combustion space that is open on one side; a combustion device provided in the combustion chamber to combust air-fuel mixture made by mixing fuel with air; and a radiator configured to be heated by heat generated from the combustion device and including a radiation plane configured to emit infrared radiation. The combustion device includes: a nozzle provided in a flow path of the air to inject the fuel; a tubular body including a side surface that faces a direction with a predetermined angle with respect to the radiation plane, and a plurality of voids being formed on the side surface; and an ignition device provided outside of the tubular body and configured to ignite the air-fuel mixture. The air-fuel mixture flows into the tubular body, and the tubular body releases the air-fuel mixture from the voids into the combustion chamber.