AIM:To investigate the clinical effect of high dose methylprednisolone in acute optic neuritis(AON). METHODS:Clinical features of 57 cases 69 eyes with AON were studied. RESULTS:Within prompt intravenous methylprednisolone and other synthetic treatment,the cure rate of AON reached 68%and the effective rate was 91%. CONCLUSION:High dose methylprednisolone in AON not only is reasonable and effective,but also can shorten the period of treatment.