Spinal perineural cyst rarely appears in the upper lumbar spinal region as compared it occurrence at other spinal region. These cysts seldom cause radiating pain and neurologic symptoms because the majority of these cysts involve the sacral portion of the spine. Spinal perineural cyst can be recognized incidentally on magnetic resonance imaging while differentiating other diseases that cause back pain. The differential diagnosis of symptoms is needed to rule out whether or not the intraspinal cystic mass is the actual cause of radiculopathy. We report here on a case of perineural cyst at a left neural foramen of L2-3 and the patient displayed neurologic manifestations. The patient had progressively aggravated low back pain and sciatica of two years duration. MRI well demonstrated neural compression of the left 2nd lumbar neural root. Relief of symptoms were achieved by performing posterior decompression (hemilaminectomy, fascectomy & decompression of the ligamentum flavum), excision of the cyst and posterolateral fusion of L2-3.