A heat cooking device comprises a casing, a heating chamber, and an exhaust duct having an outlet provided on a rear edge side of an upper surface of the casing such that exhaust air from an inside of the casing is blown out forward. An upper outer wall surface of a rear surface plate of the casing is covered by the exhaust duct to form an exhaust passage between the casing and the exhaust duct. A guidance part is provided inside the exhaust passage, and guides the water infiltrating into the exhaust passage through the outlet of the exhaust duct, downward inside the exhaust passage.