Objective: Adult stem cells are undifferentiated cells that can be derived from different parts of the body including bone marrow, adipose tissue and blood. They can differentiate into many different cell types such as bone, muscle, hepatocytes, neuron and fat. One of the best-characterized adult stem cells is the mesenchymal stem cells (MSCs) that can be isolated from adipose tissue by a minimally invasive procedure. These properties have generated tremendous interest in the potential use of MSCs for regenerative medicine. The aim of this study is the isolation and characterization of adipose tissue derived mesenchymal stem cells from different sources of adipose tissue such as heart, abdomen and breast. Materials and Methods: Fragments of adipose tissue minced and digested with collagenase. The resulted soap was centrifuged, the pellet was put on Ficoll solution and the second layer was transferred into a tube and cultured in DMEM culture medium. For characterization of ASCs, flow cytometry analysis was performed for cell surface markers including CD14, CD34, CD45, CD44, CD105 and CD166. Results: ASCs was cultured and expanded for many-fold in sequential passages. Flow cytometry analysis of cell surface markers of the isolated cells exhibited lack of expression for CD45, CD14, CD34 and a high level expression for CD166, CD105 and CD44. Conclusion: Immune gene transfected of autologous MSCs in patients with cancer is one of the most important applications of these cells in cell therapy. It is shown that MSCs are able to engraft in several tissues, migrate to sites of injury and differentiate into regenerating tissue. By considering the similarity between the pattern of surface markers in ASCs and bone marrow derived mesenchymal stem cells and their potential differentiation, the result of this investigation point to the important of adipose derived MSCs for both gene and cell therapy in cancer and other human disorders.