Abstract:he mesenchymal stem cells (MSCs) derived from bone marrow of the adult Guanzhong dairy goats were used to be induced to differentiate into osteoblast phenotype in vitro. The results showed that, after induced for 4~5 d by dexamethasone, beta-glycerophosphate and ascorbate-2 phosphate, the volume of some cells of the goat MSCs gradually largened and changed their form from spindle/polygon to cuboid/ovoid; With the induce time continuing, the numbers of the cuboid/ovoid cells continuous increased; At 15th day, there were many cuboid cells, and the modality of the cells changed from cuboid to ovoid; At 25th day, the oval and cuboid cells accumulation were observed. And the osteoblasts differentiation rate of the cells was 90.2% ± 2.97%. These indicated that the goat MSCs were induced to differentiate into osteoblast phenotype and the new born cells demonstrated positive staining for alizarin red and alkaline phosphatase (ALP). These results suggested that the MSCs were induced to differentiate into osteoblst phenotype in vitro. Accordingly, the data can provide a scientific foundation with cellular mode and further study for the bone defaults repairing.