[OBJECTIVE]:To investigate the influence and mechanism of salvianolic acid B (SalB) on apoptosis inhibition in rat bone marrow-derived mesenchymal stem cells (BMSCs) induced by hypoxia and serum deprivation (hypoxia/SD).[METHODS]:SalB concentration of 0.1,1,10 or 100mg/L (drug groups) were investigated for their ability to inhibit apoptosis in rat BMSCs.BMSCs in both the apoptosis model and drug groups were cultured under hypoxic conditions for 6 h,after which cell apoptosis and change in mitochondrial membrane potential (MMP) were detected using flow cytometry.Activation of caspase-3 was detected using west blot analysis.[RESULTS]:Hypoxia/SD induced apoptosis in rat BMSCs.The early apoptosis rate was lower in the druggroups compared to the apoptosis model group (P＜0.05).SalB was found to inhibit the reduction in MMP and decrease the activation of caspase-3.[CONCLUSION]:0.1,1 and 10 mg/L of SalB inhibits activation of caspase-3 and early apoptosis of rat BMSCs induced by hypoxia/SD and could therefore enhance the survival rate of grafted stem cells.