Objective: We present the first report in the literature on the bilateral tentorial herniation after the endovascular embolization of a large brain arteriovenous fistula. Clinical presentation: A 7-year-old boy who had chronic headaches underwent computed tomography (CT), which disclosed an abnormal intracranial mass in the right cerebral hemisphere. Magnetic resonance imaging (MRI) scan shows multiple tortuous signal void lesions suggesting vascular lesions. Cerebral angiography revealed a cerebral arteriovenous fistula with a very large venous pouch. The patient was referred to Beijing Tiantan Hospital for further treatment. Intervention: Partial embolization of the AVF from the arterial side was initially attempted successfully resulting in a reduction of the shunt flow. The patient developed swelling of his right hemisphere and caused bilateral tentorial herniation. Although the decision was made to attempt resection of the thrombosed varix, there was yet any recovery of blindness caused by herniation. Conclusion: Our study suggests that tentorial herniation can cause compression of optic tracts leading to complete blindness with conscious clarity. Clinicopathologic considerations of the complete bilateral blindness produced from the above events are discussed in detail. Prevention is the only therapeutic approach to this type of visual catastrophe. The outcome of radical surgical intervention for this kind of patients is still unclear and further investigation should be given. © 2009 Elsevier Ireland Ltd. All rights reserved.