Objective: This study is an attempt to examine the transdifferentiation of bone marrow stromal cells (BMSCs) into tyrosine hydroxylase immunoreactive cells in parkinsonian rats associated with angiogenesis. Materials and Methods: In this study, Sprague-Dawley rats received unilateral stereotaxic injections of 6-hydroxydopamine(6-OHDA) into the left corpus striatum and then were divided into two groups. One group, the negative control, received only medium while the other group was treated with BMSCs. BMSCs were harvested from femur bones, labeled with bromodeoxyuridine (BrdU) and then transplanted into parkinsonian rats, where a behavioral study and immunohistochemistry were used to evaluate the treatment. Results: The results showed statistically significant improvement in rotational behavior. Anti-BrdU antibody showed engraftment of the transplanted cells at the transplantation site. Additionally, double immunolabeling confirmed that these cells were positive for neurofilament- 200 and tyrosine hydroxylase (TH). Conclusion: It may be concluded that BMSCs transplants could engraft and differentiate into TH immunoreactive cells which may cause recovery from motor deficits. Also, BMSCs may contribute to angiogenesis at the transplantation site.