Background aims: Fracture is one of the commonest bone problems occurring as a result of injury in normal bone or as a consequence of bone weakening. Mesenchymal stromal cells (MSCs) are attractive candidates for cell-based bone regeneration. The aim of the study was to evaluate the therapeutic potential of mesenchymal stromal cells (MSCs) on the healing process of comminuted bone fracture and to determine the changes found in bone markers of [serum alkaline phosphatase (ALP) and osteocalcin (OCN)] with the process of fracture healing in mice. Methods: Forty female mice were randomized into four groups: group I consisted of 10 mice with fixed comminuted fractures; group II consisted of 10 mice with fixed comminuted fractures and received phosphate buffer saline (PBS); group III consisted of 10 mice with fixed comminuted fractures that received intra-lesional MSCs; group IV consisted of 10 mice with fixed comminuted fractures and received intra-peritonial MSCs. Samples were collected before fracture, 3 weeks and 8 weeks after fracture to determine the serum ALP and OCN gene expression. Radiological examination was done 3 and 8 weeks after fracture. Mice from each group were sacrificed for histopathological examination 3 and 8 weeks after fracture. Results: The MSC transplant improved the fracture healing which was confirmed by osteogenic marker (ALP & OCN), radiological and histopathological examination.