Two cases of apparent ophthalmologic toxicity which occurred during treatment with cis-dichlorodiammineplatinum(II) (DDP) are described. In the first case, a patient with testicular carcinoma developed papilledema after three courses of DDP and adriamycin therapy. In the second case, a patient with breast cancer developed retrobulbar neuritis after three courses of DDP therapy. The differential diagnosis and possible explanation for these toxic effects are discussed.