Objective To study the effect of lentiviral vector of MicroRNA-126 on survival differentiation of mesenchymal stem cells under ischemic condition.Methods Lentiviral vector of MicroRNA-126 was constructed and then transfected into mouse mesenchymal stem cells (MSCs).Flow detection was used to detect transfection ability and synthesis of collagen type Ⅰ.ELISA was used to detect osteocalcin,Insulin-like growth factor 1 (IGF-1) and transforming growth factor-β (TGF-β) in cell culture supernatant.Mandibular bone defect model was constructed and then injected the hydrogel mixed with MSCs.After 48h,the survival rate and proportion of differentiation into osteoblasts was determined.Results Flow results showed lentiviral vector of MicroRNA-126 could transfected into MSCs.ELISA results showed that MicroRNA-126 lentiviral vector transfected MSCs secreted more bone gla protein and IGF-1 and TGF-β,which increased by 1.43,1.87 and 2.63 times compared with the control virus treated group.Animal experiments showed the number of stem cells survived in the MicroRNA-126 group was 4.56 times that of the control group and the percentage of MSC differentiation into osteoblasts was 75％,which is 3.95 times more than that in the control group.Conclusion The research shows that lentiviral vector of MicroRNA-126 could maintain MSCs survival and differentiation under ischemic condition.