The data recorded from 170 autopsies of patients with Behçet's syndrome in Japan during the period from 1961 to 1976 were analyzed. The patients had been in the second to the eighth decade of life, and the ratio of males to females was 5 to 2. A wide spectrum of pathologic findings was observed, with involvement of neurologic, ophthalmic, cardiovascular, pulmonary, gastrointestinal, visceral, genitourinary, and mucocutaneous systems. Some of the common acknowledged clinical features of the syndrome, such as oral ulcers, synovitis, retinal and cutaneous vasculitis, and venous occlusions, were underreported. This apparent discrepancy in an autopsy series may be due to the effects of treatment or the healing process, as well as to the possible incompleteness of the postmortem examination. The accessibility of recorded data in a national autopsy registry offers a unique opportunity for review of the pathologic features of Behçet's syndrome.