Objective To confirm the stimulating effect of simvastatin on BMSCs of SD rats osteogenic differentiation, and to further study the role of Wnt signal ing pathway in this process. Methods BMSCs derived from the tibia and femur of 6-week-old female SD rats were cultured in vitro．Two groups were establ ished: control group and experimental group. After the 2nd passage, the cells of experimental group were treated with simvastatin (1 × 10-7mol/L) and the cells of control group with absolute ethyl alcohol and PBS. ALP staining was used at 7 days and von Kossa staining was appl ied at 28 days to assess osteoblastic differentiation and mineral ization. Real-time quantitative PCR was performed to evaluate theexpressions of Axin2, β-catenin, osteocalcin (OC), frizzled-2, Lef-1, and Wnt5a mRNA at 7 days and 14 days after simvastatin treatment. Results The observation of inverted phase contrast microscope showed that the majority of cells were polygonal and triangular in the experimental group, and were spindle-shaped in the control group at 7 days. The ALP staining showed blue cytoplasm, the positive cells for ALP staining in the experimental group were more than those in the control group at 7 days. The von Kossa staining showed that mineral ization of extracelluar matrix at 28 days in two groups, but the mineral ization in the experimental group was more obvious than that in the control group. The expression of Axin2 mRNA was significantly lower, and frizzled-2, Lef-1 mRNA were significantly higher in the experimental group than in the control group (P lt; 0.05) at 7 days, while the mRNA expressions of Axin2, OC, frizzled-2, Lef-1, and Wnt5a were significantly higher in the experimental group than in the control group at 14 days (P lt; 0.05). Conclusion Simvastatin can promote the osteogenic differentiation of BMSCs and change the expression of mRNA of some components of Wnt signal ing pathway.