At the age of 20 years, a Japanese man with recurrent oral aphthae, genital ulcers, folliculitis, erythema nodosum, episodic arthritis and epididymitis was diagnosed as having Behcet's disease (BD) in 1966. He has had active ocular manifestations of BD since 1990. These symptoms recurred and never abated for a long period of time. A right renal cell carcinoma developed and he underwent right nephrectomy in April 1996. Treatment with interferon-alpha was started from June 1996 as supplemental chemotherapy. No active phase developed during administration of IFN-alpha. We suggest that IFN-alpha may play a role as an immunomodulatory agent in BD.