We report a rare case of intracranial hypotension that was complicated by a subdural hematoma following spine surgery. Intraoperatively, we did not notice any breach of the dura. However, the patient continued to have fluid leakage from the inferior edge of the lumbar incision. During revision surgery, a small dural tear was identified and repaired. It is likely that a small dural tear was overlooked or the dura was weakened during the initial operation and caused a subdural hematoma associated with intracranial hypotension.