Interferon (IFN) has antiviral, antiproliferative and immunomodulating effects. The various types of interferon are widely used in the treatment of many diseases in clinic. Interferon-associated ophthalmologic complication is a relatively rare side effect in the process of treatment, and has diverse clinical manifestations, which can mainly be divided into: interferon associated retinopathy, interferon associated optic neuropathy and atypical ocular side effects. Interferon associated retinopathy, the most common form, manifests as scattered white cotton wool spots and/or small retinal hemorrhages around the disc and through the posterior pole. Most of the patients are visually asymptomatic and do not require any treatment. These lesions can resolve over time. But a minority of patients may develop serious interferon associated ophthalmologic complications, such as ischemic optic neuropathy, retinal vascular obstruction, macular edema, Vogt-Koyanagi-Harada disease. These patients often complain of visual damage which may lead to irreversible visual impairment. For these cases, the IFN therapy must be terminated, and aggressive early interventions must be offered, such as systemic hormone treatment, intravitreal injection of anti-VEGF agents and retinal laser coagulation, etc. In order to avoid permanent visual impairment, the physicians or ophthalmologists should be highly aware of these diseases, and ask detailed questions about the systemic disease and the history of any eye diseases, and pay attention to high-risk factors: hypertension, diabetes mellitus, diabetic retinopathy, or a history of Vogt-Koyanagi-Harada disease. For high risk patients, periodically eye examinations are necessary.