Stem cell therapy is a promising therapy that figure out a new approach to treat diabetes mellitus. In this study, adipose derived stem cells were differentiated in vitro into insulin-producing cells by using chemical agents such as retinoic acid, nicotinamide and exendin-4, glucose. Then, the authors evaluated this differentiation process by appropriate assays. The results showed that the induced cells expressed some characteristics of insulin producing cells as forming clusters like islet cells, positive staining with dithizon dyes, expressing of specific genes that related to insulin secretion, regulating insulin secretion by the change of glucose concentration.