The Stem Cells are natural as well as organic cells which have ability to be differentiated into other types of cells of body and can multiply to produce similar stem cells. As per the standard definition, a stem cell possesses two properties; firstly the Selfrenewal means ability to undergo numerous cycles of cell division by sustaining its undifferentiated status and secondly the Potency that is the ability to be differentiated into particular cell types. In human being, two broad types of stem cells have been described, the Embryonic Stem Cells (ESCs) which are derived from the inner cell mass of blastocyst and the Adult Stem Cells (ASCs) which are present in the various tissues of body. The aim of this review study is to bring actual facts between the ESCs and the ASCs in human. Related literatures on the subject reviewed through electronic database like PubMed, NCBI, Google Scholar, Web of science etc. The final conclusion was achieved by comparing their structural and functional similarities, dissimilarity, potency, advantages, disadvantages and related recent clinical advancement as regenerative medicine. A number of diseases are being claimed to be treated by the pleuripotent ESCs including blood & immune-system related genetic & malignant disorders, Juvenile diabetes, Parkinson's, Blindness and Spinal cord injuries. On the one side, the uses of the ESCs in research & therapy is controversial as they are derived from 5 days old embryos generated by IVF clinics designated for scientific research and on the other side the ASCs treatments are being employed successfully in many illnesses in last many years especially for treating leukemia & related bone cancers through bone marrow implants. The utilizing ASCs in research and therapy are not as divisive and controversial as that of the ESCs, because the construction of the ASCs does not require the damage of an embryo.