Mobile intraspinal tumours have rarely been reported. In most cases, mobile tumours such as schwannomas or ependymomas were located in the cauda equina. Perusal of the literature revealed only two reports of mobile schwannomas in the cervical and thoracic regions. We report a case of thoracic schwannoma which migrated twice in successive operations resulting in negative exploration in the expected area. The aim of this report is to remind the surgeons about the possibility of migration of intradural-extramedullary tumour.