PURPOSE: To make thawing cook, etc., of a material to be heated and cooked uniform by supplying microwaves from upper and lower ports formed at a heating cooking chamber when the material to be heated and cooked is thawed and cooked by supplying the microwave to the chamber.

CONSTITUTION: Upper and lower ports 6, 7 for supplying microwaves are formed at one sidewall for forming a heating cooking chamber 3. A waveguide 14 is so arranged at a rear side of the one sidewall as to enclose the ports 6, 7, and a magnetron 15 for generating the microwave is arranged outside the waveguide 14. On the other hand, a rotary tray 8 is arranged in an inner bottom of the chamber 3, a weight of a material to be heated and cooked to be placed on the tray 8 is detected by a weight sensor 9, and the tray 8 is rotated by a turntable driving motor 10. Thus, the microwaves are supplied from the ports 6, 7 to be emitted to the entire material to be heated and cooked. Accordingly, thawing of frozen food can be uniformly conducted.