AimTo explore the effect of stromal cell-derived factor-1α (SDF-1α) on proliferation and vessel-like structure formation in vitro rat bone endothelial progenitor cells ( EPC).MethodsEndothelial progenitor cells derived from rat bone were isolated by method of micropore and characterized by immunofluorescence technique with EPC special markers VEGFR-2/CD133.And the abilities of vessel-like structure formation and cell proliferation were detected by the methods of cell culture, MTT assays after treated with 1, 10, 100 μg/L SDF-1α and CXCR4 antagonist AMD3100.Results The EPC derived from rat bone arrayed into a cobblestone-like structure and formed vessel - like structure， at the same time, EPC differentiated more maturer and expressed endothelial cells special markers vWF. Two groups of SDF-1α （10 and 100 μg/L） significantly promoted EPC proliferation(n=5, P<0.01)， and three groups of SDF-1α （1, 10 and 100 μg/L）significantly promoted EPC vessel-like structure formation with a dose dependent manner (n=5, P<0.01).All these effects were significantly attenuated by AMD3100.ConclusionSDF-1α possibly plays a critical role in regulating proliferation and vasculogenesis of rat bone-devived EPC.