A 34-year-old woman was admitted because of severe orthostatic headache. On CSF examination, the opening pressure was below 30 mmH2O. A spine MRI showed a large collection of extradural fluid indicating that CSF leaked into the extradural space. The headache was resolved by an epidural blood patch. We present a patient with a syndrome of CSF hypovolemia, whose spine MRI showed a large amount of leaked CSF in the epidural space of the spine.