Objective To examine the effect of recombinant human bone morphogenetic protein-2(rhBMP-2) on NIH3T3 cells. Methods The NII-UT3 cells~cultured in DMEM with 50 ug/L rhBMP-2. the proliferation ability, alkaline phos- phatase (ALP) activity and osteocalcin (0C) quantity of NIH3T3 cells were investigated. Results The cells showed decreased proliferation ability but enhanced ALP activity and OC quantity. Conclusion 50 1rg/L rhBMP-2 can transform NIH373 fibroblasts to osteo-like cells.