We report a case of Wegener's granulomatosis (WG) with central nervous system (CNS) involvement in a woman who complained of bilateral visual disturbance. The intracranial necrotizing granulomatous lesion was confirmed by MR imaging and brain biopsy. After high-dose oral corticosteroid treatment, not only clinical manifestations but also laboratory tests improved. Moreover, the CNS lesion completely regressed. This suggests that high-dose corticosteroid alone might be effective in treating WG with CNS involvement.