Atypical teratoid/rhabdoid tumors (AT/RT) are highly aggressive malignant primitive neoplasms that commonly occur in children younger than 2 years of age. The prognosis is generally dismal with a median survival time of <1 year. The majority of AT/RT occur in the posterior fossa and less frequently the supratentorium. Primary pediatric spinal AT/RT are exceedingly rare and only 15 cases have been reported to date. Here we report a very unusual case of primary spinal AT/RT extensively involving the spinal cord from T11 down to the cauda equina. In this patient, the tumor was highly aggressive and resulted in extensive dissemination into the nerve roots and paraspinal soft tissue rapidly resulting in the patient's death 1 month after diagnosis. to the best of our knowledge, this degree of involvement of the spine by a primary AT/RT has not been described before.