Cerebral venous thrombosis presenting with subarachnoid hemorrhage (SAH) is very rare. We report a case of cerebral venous sinus thrombosis as an initial manifestation of SAH. A 14-year-old boy was admitted with progressive headache, nausea, vomiting, diplopia, and gait disturbance. Cerebral computed tomography scan showed a widely SAH in the basal cisterns, bilateral sylvian fissures, and anterior interhemispheric fissure. Cerebral angiography was performed to detect any aneurysm in intracranial vasculature as a cause of SAH; however, the totally thrombosed superior sagittal sinus, galenic vein, and straight sinus were the sole abnormal findings.