Objective: Bone marrow stromal cells (BMSCs) transdifferentiated to oligodendrocyte-like cells (OLCs), were transplanted to rats subjected to contusion SCI, and their role in remyelination and motor improvement was studied. Materials and Methods: Under sterile conditions BMSCs were obtained from femur of adult rats and then differentiate to OLCs by different growth factors. For in vivo studies 74 adult female rats were subdivided to 5 groups. In 1st group or Sham only laminectomy was performed at T13 level, whereas in other groups after laminectomy a contusion SCI was done. In 2nd group only SCI was done (C1) and in 3rd group (C2) 9 μl normal saline was injected intraspinally (IS). In 4th group (E1) BMSCs were injected IS, in 5th group (E2) OLCs were transplanted IS. In all groups one day before SCI up to 12 weeks after it, motor improvement was assessed by BBB test. At the end of 12th week, spinal cord segments T12-L1 were studied by histomorphology and immunohistochemistry to determine histologic changes and the extent of cell replacement at the injury site. Results: Immunohistochemical and RT-PCR studies by means of fibronectin, CD44, CD45 and Oct-4 indicated that following 4th passage, a considerable percentage of cultured cells were undifferentiated BMSCs. Investigation of nestin at the end of preinduction stage showed that DMSO and RA differentiated BMSCs to NELCs. Studying O4 marker indicated that during the induction stage the combination of bFGF, PDGF, HRG and T (10 ng/ml) can have a prominent role on differentiation of NELCs to OLCs. The findings of BBB functional test showed a spontaneous gradual and restricted motor improvement in control groups. In all experimental cell-therapy groups a significant motor improvement could be seen again control groups. In E2 group versus E1 not significantly better motor movement scores could be seen. Histomorphometric findings indicated, cavity formation significantly decreased and spinal cord section area significantly increased in epicenter transplantation of experimental groups versus control groups. Number of detected transplanted cells at cranial and caudal regions were more than epicenter of same transplanted group. On base of MBP expression, mean percentage of transplanted cells differentiated to myelinogenic cells in E2 group was significantly more than E1 group. Conclusion: DMSO and RA induce differentiation of BMSCs to NELCs, and a combination of bFGF, PDGF, HRG and T (10ng/ml) induces differentiation of NELCs to OLCs. Intraspinal transplantation of these OLCs, like intraspinal transplantation of BMSCs resulted motor improvement in contusion spinal cord injury.