This paper reports an autopsy case of a 5-year and 11-month-old girl with generalized subcutaneous lipomatosis, megalencephaly, and macrodactyly. Marked emaciation and poor prognosis were the characteristic findings of this case. We thought that this case was identical with a rare syndrome which was initially reported by BANNAYAN in 1971. Autopsy disclosed diffuse lipomatosis in the thoracic and abdominal cavity, and infiltration of fat tissue to the pancreas. Hyperplasia of the small intestinal mucosa and Peyer's patch, and a pedunculated polyp of the sigmoid colon were the unique findings which could not be seen in the previously reported cases.