Spontaneous spinal epidural hematoma (SSEH) is a rare disease entity; its causative factors and the factors determining the outcome are still controversial. We reviewed our clinical experiences and analyzed the various factors related to the outcome for SSEH. We investigated 14 patients (11 men and 3 women) who underwent hematoma removal for SSEH from April 1998 to August 2004. We reviewed age, gender, hypertension, anticoagulant use and the preoperative neurological status using the Japanese Orthopaedics Association score by examining medical records, operative records, pathology reports, and radiographies, retrospectively. We were checking for factors such as the degree of cord compression owing to hematoma and the extent and location of the hematoma. Most patients included in the study were in their twenties or fifties. Four hematoma were located in the cervical region (29%), three were cervicothoracic (21%), four were thoracic (29%) and three were in the lumbar (21%) region and also 12 were located at the dorsal aspect of the spinal cord. In all cases, the neurological outcome improved after the surgical operation. There was a statistically significant difference between the incomplete and complete neurological injury for the preoperative status (P<0.05). The neurological outcome was good in those cases that had their hematoma removed within 24 h (P<0.05). The patients with incomplete neurological injury who had a surgical operation performed within 12 h had an excellent surgical outcome (P<0.01). Spontaneous spinal epidural hematoma was favorably treated by the means of a surgical operation. The favorable factors for SSEH operations were incomplete neurological injury at the time of the preoperative status and the short operative time interval.