Forty-six patients with Behcet's disease were studied. Of those, 37 were Saudi and 9 were non-Saudi Arabs. Maleto-female ratio was 4.1:1. One hundred percent had mouth ulcers, 91% genital ulcers, 65% ocular involvement, 61% skin lesions, 59% joint involvement (nonerosive), 35% central nervous system manifestations, 26% gastrointestinal involvement, 26% vascular lesions, 11% psychiatric problems, and 11% pulmonary involvement. Only one patient had renal involvement which was documented by biopsy. In 72% of the patients, HLA-B5(51) was positive.