Abstract: The present invention provides a method of preparing pressure-treated rice characterized by placing washed polished rice directly or as enclosed in a container into a liquid within a pressure chamber and applying a high pressure to the pressure chamber for a suitable period of time, and a container for cooking the pressure-treated rice in a microwave oven characterized in that the cooking container comprises a container body, a closure for the container body, and a partition provided inside the container body, the partition having a multiplicity of steam ports and being disposed in the interior of the container body for dividing the interior into an upper portion for accommodating the rice therein and a lower portion for accommodating therein water for steaming the rice. The method readily affords the pressure-treated rice, which can be cooked to a state suited to eating when heated for a short period of time with a reduced likelihood of impairing the flavor, taste and nutrients.