PURPOSE: To reduce the generation of smoke and make the time for heat cooking shorter by providing a second heater which is located between a net and a receiving plate for receiving an object to be heated and providing oxidation catalyst on the receiving plate so that fats and oils dropping onto said plate are oxidized and decomposed.

CONSTITUTION: An object 3 to be heated such as a roast fish which produces a large amount of fats and oils is cooked. Since the surface temperature of a receiving plate 23 rapidly becomes higher than 350°C by means of a second heater 25, even if fats and oils drop from the object 3 onto the plate 23, they are oxidized and decomposed to carbon dioxide and water by oxidation catalyst 24 on the plate 23. The catalyst 24 holds paricles 27 of oxides in the voids formed in entangled ceramic fibers 26, in which the voids is as high as tens of %, and hence the oxidation of fats and oils is easily effected. And the fats and oils scattered from the object 3 are sucked by an exhaust suction fan 11 provided at the rear of a main body 1 and passed through catalyst 12 so that they are decomposed to carbon dioxide and water, resulting thereby in reduced generation of smoke. Preferably, the surface temperature of the catalyst 24 on the side of the second heater is 350-400°C or higher.