Radiological and intraoperative findings of the presented case of spontaneous acute spinal subdural hematoma. T1-weighted magnetic resonance imaging showed an isointensive lesion situated at the T9 level, ventral to the spinal cord (A). T2-weighted magnetic resonance images showed the lesion was a well-demarcated, oval-shaped extramedullary mass at the T9 level (B, C). An emergency laminectomy from T8 to T10 was performed and only a hematoma was found during the operation (D) and it was successfully evacuated (E). Postoperative sagittal T1-weighted contrast enhanced (F) and T2-weighted (G) magnetic resonance imaging showed total removal of that hematoma.