A 32-year-old woman visited our department because of repeated regurgitation of food, and was diagnosed with rumination syndrome based on possession of symptoms typical for it. Although rumination syndrome is classified as a functional esophageal disorder according to the Rome II criteria, it is not well known in Japan, and there have been no previous reports of it in an adult with normal intelligence. Since patients with rumination syndrome are often misdiagnosed and receive unnecessary treatment, awareness of it by physicians is important.