Objective To summarize the feasibility and safety of the islet cells co-transplantation with bone marrow mesenchymal stem cells (BMSCs) in the treatment of diabetes. Methods The latest progress and new achievements of islet cells transplantation and BMSCs transplantation in treatment of diabetes in the world were analyzed and reviewed. Results At present, the pancreas transplantation and the islet cells transplantation were mainly treatments for diabetes, the pancreas transplantation had disadvantages of large trauma and high mortality; the islet cells transplantation was safe, but had disadvantages of strong rejection, and the survival time of islets cells were short which affected the treatment effect of diabetes. The BMSCs co-transplanted with the islet cells could prolong the survival time of islet cells and could alleviate the rejection in body, so the co-transplantation can be more effective in treatment of diabetes. Conclusion The BMSCs co-transplant with the islet cells could reduce the rejection in vivo, reduce the inflammation in vivo, prolong the survival time of islet cells, extend the time of normal glucose, which may become the new treatment method for the diabetes.