The image projection apparatus includes an exhaust air outlet through which an exhaust air flows out from an inside of the apparatus to an outside thereof, an air inlet through which an external air flows in from the outside of the apparatus to the inside thereof, a temperature detector which detects a temperature of the external air flowing into the inside of the apparatus through the air inlet, and a controller which performs a protection operation when one of a predetermined temperature corresponding to a temperature of the exhaust air and a predetermined temperature change caused by flowing in of the exhaust air through the air inlet is detected by the temperature detector. The apparatus enables quick detection of a state in which the exhaust air outlet is blocked to perform the protection operation.