Spinal arachnoid diverticula is a very rare disease of congenital and acquired frorms. Most of cases have neurological symptoms as seen in spinal cord tumors. Authors report a case of congenital spinal arachnoid diverticula mainly involved in lumbar area. this patient is 11 year-old Korean male with complaints of limping of both legs and bilateral equinovarus deformities. Spastic paraparesis is observed in neurological examination. characteristic radiographic findings are observed in simple T-L spine and pantopaque myelogram. Review of literature is submitted.