Forty patients with melanocytoma of the optic disc were evaluated to determine their clinical variations and behavior. Follow-up examination of 1 to 19 years was obtained in 27 patients. Of the 27 lesions, four (15%) showed a slight increase in size, and one tumor (4%) decreased in size. The remaining 22 tumors (81%) have not yet demonstrated ophthalmoscopic changes. In spite of occasional growth, the melanocytoma is a benign tumor that requires no treatment.