To introduce the lasted advance of research on cytokine in the process of union-fracture as well as cl inical appl ication. Methods The related biomedical research materials at home and broad were consulted and analyzed.Results Cytokines participate in and promote the process of union of fracture. Conclusion Nowadays, there are more detailed study at the level of cells. But the mechanism of interaction between cells has still not completely been known in the process of union-fracture. Therefore, further elucidating function and mechanism, especially interaction between cytokines is what we are gong to solve in the future.