We herein report a case of disseminated Mycobacterium avium infection that involved both optic nerves, the conjunctiva, the right lower lung, and multiple skin lesions, including a thoracic nodule. The patient was a 65-year-old man without any significant medical history. The pathogen was detected in the patient's eye discharge, sputum, bronchial lavage fluid, and thoracic nodule. Anti-mycobacterial chemotherapy, including clarithromycin, rifampicin, and ethambutol, was administered, and the thoracic nodule was resected. An autoantibody to interferon-γ was detected in the patient's serum. Bilateral swelling of his optic nerves and facial dermatitis improved after initiating anti-mycobacterial chemotherapy.