Stem cells are considered an ideal tool for the supply of insulin-producing cells or repairing damaged pancreatic tissues to treat diabetes mellitus, with the possibility of unlimited sources. This cell population includes embryonic, adult bone marrow, pancreatic stem cells, extra pancreatic (such as hepatic cells) and adipose-derived stem cells. Multipotent adipose tissue-derived stem cells (ADSCs) are abundant in the human body, and thus are an ideal donor source for autologous transplantation to generate insulin-producing cells. Moreover these cells are better sources than bone marrow stem cells (BMSCs) for clinical applications, owing to minimal invasive procedures, high proliferation and multi-differentiation potential. Human adipose tissue-derived stem cells (hADSCs) may thus provide an alternative stem cell source, replacing BM-MSCs or embryonic stem cells (ESCs) for future clinical use in diabetes mellitus treatment.