The electro-oculogram has been applied in the diagnostic evaluation of eyes with malignant uveal melanoma. Typically, a marked reduction in the light peak to dark trough ratio has been reported. We studied two patients with histologically confirmed uveal malignant melanomas in whom the preenucleation electro-oculograms were normal. The electro-oculogram should be evaluated within the framework of the clinical examination and other ancillary tests in the diagnostic evaluation of a suspected uveal malignant melanoma.