Objective:To evaluate effect of bone marrow mesenchymal stem cells (BMMSCS) on albino rats^, submandibular salivary glandafter intraglandular injection of bleomycin (BLM). Methods: Forty- two rats were randomly divided into three groups. Group I (n=18): was subjected to intraglandular injection of a single dose of 1.5mg/kg of bleomycin. Group II (n=18): was subjected to intraglandular injection of a single dose of 1.5mg/kg of bleomycin dissolved in distilled water. After four weeks; rats were subjected to another injection of (1 x 10 ⁵) cells of BMMSCs. Group III (n=6): was subjected to intraglandular injection of 0.05 ml of distilled water in the left submandibular salivary gland and rats were sacrificed after five weeks from starting the study. Tissue sections were stained with Toluidine blue then were subjected to digital image analysis followed by one- way ANOVA statistical analysis.