Diastematomyelia (DM); is a condition characterized with division of the spinal cord into two hemicords by a cartilaginous, osseous or fibrous septum. In about 50% of the cases, the spinal cord is involved, while in the remaining half the hemi-cords are contained in subarachnoid space or across the spinal canal. DM, can involve all segments of the spinal cord. A 27 years old female patient admitted with complaint of backache and urinary for about a year. Computerized tomography (CT) scan and magnetic resonance imaging (MRI) revealed that the spinal cord dividing into two hemicords by an osseous septum from forward to backward at the level of L2-3. There was also evident pedicular bone defect on the right sight of the vertebrae at the level of L5. We present this case due to rarity of association of DM and pedicular bone defect and its silent course till this adult age. ©2007, Fırat University, Medical Faculty