PURPOSE: To easily extract coffee having excellent taste and flavor at a low cost by immersing roasted and crushed coffee beans in a vessel containing a prescribed amount of water optionally in a state packed in a water-permeable bag and irradiating the beans with microwave.

CONSTITUTION: The direct immersion of coffee beans in water is carried out by spreading a water-permeable membrane or net in water near the water surface to prevent the flotation of the beans on the water surface. In the case of sealing the beans in a water-permeable bag, the flotation of the bag is prevented by putting a weight to the bag or fixing the bag near the bottom of the vessel with a clip. In either case, the beans are irradiated with microwave in water for a prescribed period to obtain the extracted liquid.