An injection molding machine includes a heating cylinder provided with a gas inlet, a screw, a gas cylinder, a pressure reducing valve configured to reduce a primary pressure of a gas from the gas cylinder to a secondary pressure, a gas supply portion configured to supply the gas at the secondary pressure to the gas inlet, a secondary pressure detection device configured to detect the secondary pressure, and a controller. The controller is configured to detect an abnormality by comparing a set pressure set in advance in the injection molding machine with the secondary pressure.