A 31-year-old male was diagnosed as having chronic myelogenous leukaemia and has been treated with hydroxyurea and interferon-alpha since February 1995. After 16 months, he complained of low-grade fever and a cough. Bilateral hilar lymph node enlargement was detected on the chest X-ray film and multiple subcutaneous erythematous nodules appeared. A skin biopsy revealed subcutaneous sarcoid granuloma. Two months after the cessation of interferon therapy, the subcutaneous nodules and the hilar lymph node enlargement resolved. It is possible that continuous interferon administration can promote granuloma formation in sarcoidosis by activating T cells and macrophages.