Objective To investigate plasticity of marrow-derived stem cells,possible mechanisms and application. Methods The recent literature concerned plasticity of marrow-derived stem cells was extensively reviewed. Results Although stem cells plasticity has not been proven, there is more and more evidenceto show that the stem cells may have the plasticity and at least four differentmechanisms are explained.Conclusion The extensive research will be required. If the plasticity is proven, adult stem cells can be used for more therapeutic purposes. For example, the use of stem cells from bone marrow may correct geneticor degenerative disorders of a second organ from which stem cells are more difficult to isolate.