A 48-year-old woman presented with acute voiding difficulty, numbness and weakness of both lower extremities. Magnetic resonance imaging (MRI) showed an intramedullary hemorrhagic mass that extended from T9 to T10. T8-T10 laminotomy and surgical removal of the hemorrhagic mass was performed. The pathological diagnosis was hematoma. Her neurological status remained the same after the operation. At 5 days post-operation, the patient suddenly became paraplegic, and MRI that was immediately performed revealed a recurrent intramedullary hemorrhage. Emergent surgical evacuation was performed. Again, histological examination showed only hematoma, without any evidence of abnormal vessels or a tumor. A postoperative MRI revealed no abnormal lesions other than those resulting from postoperative changes. At a 9-month follow up, the patient could walk a short distance with the aid of a walker. Because spontaneous intramedullary hemorrhage with unknown etiology is very rare, it is essential to perform a meticulous inspection of the hemorrhagic site to find the underlying cause. Repeated hemorrhage can occur; therefore, close observation of patients after surgery is important in cases without an apparent etiology. Urgent surgical evacuation is important to improve outcomes in these cases.