Purpose.We report an unusual case of mucolipidosis IV in a patient of African ancestry, with intracytoplasmic inclusions of the corneal endothelium found on electron microscopy.Method.Clinical description with light and electron microscopy.Results.We describe a case of mucolipidosis IV diagnosed in a patient of African ancestry after penetrating keratoplasty. Electron microscopic evaluation revealed intracytoplasmic inclusions in both the corneal epithelium and endothelium.Conclusion.The diagnosis of mucolipidosis in a patient of African ancestry is unusual, as this genetic disorder is found predominantly in individuals of Jewish descent. Corneal endothelial involvement in mucolipidosis IV has not previously been reported.