The purpose of this study was the evaluation of retinal abnormalities during a treatment with natural interferon (IFN-alpha for chronic hepatitis C. Retinal hemorrhages and optic disk edema were found in a 40-year-old woman during IFN-alpha therapy. The disk edema and retinopathy resolved after the INF was discontinued. Although retinal abnormalities correlated with IFN therapy have been described recently by some authors, the pathogenesis is still unclear. Anterior ischemic optic neuropathy occurring in a patient treated with IFN is a probable complication of the therapy.