Regenerative therapy has begun to be clinically applied in humans and dogs to treat neurological disorders, such as spinal cord injury (SCI). Here, we show the therapeutic potential of transplantation of cultured canine bone marrow stromal cells (BMSCs) into mice with SCI. Canine BMSC transplantation therapy was performed, immediately after the spinal cord was injured. Canine BMSC therapy enhanced functional recovery of the hind limbs in mice with SCI. Nestin-positive cells were observed only in the lesion of mice with SCI that received BMSCs. These results suggest that canine BMSCs promote functional recovery in mice with SCI and that migration of nestin-positive cells may contribute to the efficacy of the BMSC treatment.