Abstract: ObjectiveTo investigate the effect of transfection Runx2 or siRNA Runx2 gene on the in vitro bio-characteristics of K7M2 osteosarcoma cell . Methods Scrambled plasmide，plasmids carrying Runx2 and siRNA Runx2 were transfected into K7M2 cells respectively. Runx2 protein expression after transfecting was detected with Western blot. The proliferation capacity, invasion,migration and adhesiveness were observed. Meanwhile,the apoptosis rate and cell cycle distribution of K7M2 cells in each group were detected using flow cytometry. Results Compared with control,Runx2 protein expression of K7M2 cells in the transfected or intervened Runx2 gene group were increased and reduced respectively. The proliferation capacity,migration,invasion and proliferative index in group transfected by siRNA Runx2 was decreased in comparison with control group, and the difference showed statistical deviation.However,the group transfected Runx2 showed opposite characteristics compared with control group. Neither adhesiveness nor apoptosis rate had obvious change in all three groups.There was no obvious change between the scrambled group and control group. Conclusion Runx2 can increase proliferation capacity, invasion,migration of K7M2.The potential mechanism is that it can change the cell cycle distribution,thus make cell transits to G₂/M stage more quickly.