A cooking heating apparatus has a vapor sensor for sensing the state of heating of food in a heating chamber, thus performing automatic control of the heating operation. An auxiliary exhaust opening for allowing vapor from the heated food to be introduced to the vapor sensor is formed in a region where the flow of the vapor is not influenced by a main flow of air supplied into the heating chamber and flowing towards a main exhaust opening. The vapor sensor is disposed so as to be exposed to the vapor introduced through the auxiliary exhaust opening. The condition of the vapor is therefore sensed quickly without being influenced by the main flow of air.