Autoimmune disease is typically caused by the activated self-reacted immune cells. The mainstream treatment to autoimmune disorders is composed of different mechanisms of immunosuppression. In recent years, a new subtype of T cells called regulatory T (Treg) cells have been identified to maintain the immune homeostasis in terms of suppressing the activated immune components. According to this discovery, it is suggested that treating autoimmune patients by supplementing Treg cells would be a good choice. However, due to their natural scarcity, it is difficult to isolate a desired number of Treg for this therapeutical approach. Here, we report that by using stem cells, especially the induced pluripotent stem (iPS) cells, we are able to generate a significant amount of Treg cells for the autoimmune prevention and treatment.