We have experienced acase of extradural cyst in the thoracolumbar resion. The case was a 61 year old female suffering from urinary disturbance and palsy of the perineal area. MRI and myelogram showed a cystic lesion located at the posterior part of the spinal canal and compressing the spinal cord at the Th12 L3 levels. Intra-operative findings, indicated that the cyst communicated with the subaracnoid space. After extirpating the cyst, it is necessary to clear the communicating fissure and repair the weakend or defected dura to prevent the recurrence of the cyst. The patient fully recovered from her palsy and urinary disturbance.