Fifteen patients with ocular or oculodermal melanocytosis were found after reviewing 1210 cases of histologically proven uveal melanomas. The melanoma in each of these patients developed in the eye affected with ocular or oculodermal melanocytosis and not in the unaffected eye. In the one case of bilateral involvement with oculodermal melanocytosis, the patient developed the melanoma in the eye more affected with melanocytosis. In the only case of partial ocular melanocytosis, the melanoma developed in a sector of the eye affected with melanocytosis. A comparison of the prevalence of ocular or oculodermal melanocytosis in patients with uveal melanoma with the prevalence of ocular or oculodermal melanocytosis in the general population, implies that there is an increased incidence of uveal melanomas in patients with ocular or oculodermal melanocytosis.