Parkinsonism is one of the most common aging neurodegenerative disorders. This study aims to compare the therapeutic effect of stem cell versus its conditioned medium in the Parkinsonism model. Parkinsonism was induced by daily subcutaneous injection of 0.5 mg/kg of rotenone dissolved in dimethyl sulfoxide for 28 days. Fifty rats were divided randomly into five groups: control, dimethyl sulfoxide, Parkinsonism, stem cell-treated, and conditioned medium-treated groups. Midbrain specimens were obtained for histological, immunohistochemical, and biochemical studies. Lewy bodies were observed in the Parkinsonism group in the How to cite this article: Abdelwahab S, Elsebay SAG, Fouli Gaber M, Abdel-Hafez SMN. Comparative study between bone marrow mesenchymal stem cell and their conditioned medium in the treatment of rat model of Parkinsonism.