We report an autopsy case of methamphetamine-related intracranial hemorrhage and vasculitis. The possible relationship between drug usage and the occurrence of intracranial bleeding and cerebral vasculitis in such patients is discussed. A 22-year-old woman died after an intravenous injection of unknown dose of methamphetamine. A computed tomography head scan demonstrated massive subarachnoid hemorrhage and hematoma in corpus callosum. Cerebral angiography revealed nonfilling of bilateral intracranial carotid arteries and extravasation of contrast medium from right pericallosal artery which was visualized retrogradely via vertebral artery. Postmortem studies showed cerebral edema, subarachnoid and intracerebral hemorrhage, and intracranial vasculitis in the absence of aneurysm, arteriovenous malformation or chronic hypertension. Histological findings of necrosis of blood vessel walls with destruction of the elastica and smooth muscle layer, and without leukocytotic infiltration of the blood vessel walls were observed in order of anterior cerebral, middle cerebral, vertebral, posterior cerebral and basilar arteries. These angiographic and histological evidence suggests that such hemorrhage results from the development of fibrinonecrosis in the large intracerebral vessels, in addition to a sudden rise in blood pressure.