We studied a case of herpes zoster with varicella encephalitis in which a granulomatous necrotizing vasculitis was present in the optic nerve and brain. The vasculitis was observed even in foci devoid of inflammatory reaction in surrounding tissue, and was therefore interpreted as a primary vasculitis caused by varicella. To our knowledge, this is the first time a granulomatous vasculitis has been described as an integral part of varicella encephalitis, although others have made similar observations in the eye and even in viscera. These findings support the recent suggestion that so-called granulomatous angiitis of the CNS may be caused by the varicella virus.