PURPOSE: To hold stored cooked rice at a proper temperature over a long period without drying it by providing a housing opened upward, a heating means, and a heat retaining container having a heat insulating hollow section on the peripheral wall.

CONSTITUTION: A stainless housing 20 opened upward is provided with a heater 12 as a heating means on the bottom face. A plastic heat retaining container storing cooked rice is provided with a heat retaining container main body 50 opened upward and an opening/closing cover 51 closing the opening section, and heat insulating hollow sections are formed on the bottom face and side wall of the heat retaining container main body 50. Air in the housing 10 is heated by the plane heater 12, and the side face and bottom face of the plastic heat retaining container 50 are warmed by the heated air. The outer wall heat of the warmed plastic heat retaining container 50 is mitigated by the hollow sections and is transferred to the inner wall face as an indirect heat. The heat of the inner wall face is gradually transferred to the cooked rice stored in the container 50 to serve as a heat retaining heat source.