When water temperature is high and time germinating step is short, it is hard to cook freely to individual preference, and water turbidity and bad smell are likely to occur. By germinating with immersing brown rice or rice with the germ in water at 28 to 34 degrees for 3 to 6 hours in an inner pot 3, being followed by a cooking step successively, the rice can be immersed for a necessary time at low temperature, so that germinated rice with enough content of gamma-aminobutyric acid (GABA) can be obtained without causing water turbidity or bad smell.