To observe and analyze the risk factors, clinical characteristics and treatment effect of anterior ischemic optic neuropathy(AION). METHODS: Totally 46 cases (51 eyes) of anterior ischemic optic neuropathy were retrospectively analyzed with systemic and ocular risk factors, clinical symptoms, fundus, fundus flourescein angiography (FFA), and visual field changes.To control systemic disease, systemic or topical corticosteroids, vasodilator and nerve nutrition agent were used . The therapeutic effects were evaluated. RESULTS:Patients had a mean age of 53±10 years, whose systemic diseases included hypertension, diabetes, hyperlipidemia, hypotension, cardiovascular and cerebrovascular diseases. 47.06% patients reported sudden decrease in vision, 64.71% patients with fundus examination showed optic disk gray edema, 33.33% patients with visual field defects demonstrated hemianopia, 56.82% patients with FFA showed early optic disc weak fluorescence, and advanced fluorescence enhancement. After treatment 80.39% patients improved the visual acuity and visual field. CONCLUSION:AION is a multifactor disease, hypertension, diabetes, hyperlipidemia, cardiovascular and cerebrovascular diseases are its risk factors. A sudden decline in vision, optic disc edema, hemianoptic visual field defects，optic disc early weak fluorescence and late strong fluorescence in FFA are the typical performances. Comprehensive treatment of patients can restore some vision and visual field.