Discal cysts are rare lesions that can cause radiating leg pain. Because they are very rare, their natural history and the details of the therapeutic guidelines for the treatment of these cysts are still unknown. A 30-year-old male patient presented to our institute with radiating pain in his left leg and mild back pain. Magnetic resonance imaging (MRI) revealed an intraspinal extradural cystic mass with low signal intensity on T1-weighted images and high signal intensity on T2-weighted images at the L5-S1 level. The partial hemilaminectomy and cyst resection were performed. We report a patient with low back pain and radiating leg pain caused by a lumbar discal cyst and discuss the treatment of this cyst.