The impact factor of journal provides quantitative assessment tool for grading, evaluating, sorting and comparing journals of similar kind. It reflects the average number of citations to recent articles published in science and social science journals in a particular year or period, and is frequently used as a proxy for the relative importance of a journal within its field. It is first devised by Eugene Garfield, the founder of the Institute for Scientific Information. The impact factor of a journal is evaluated by dividing the number of current year citations to the source items published in that journal during the previous two years. Stem cells are biological undifferentiated cells that can differentiate into any type of cell. These cells will divide through mitosis to produce more stem cells. They are generally found in multicellular organisms like mammals. There are again two different types of stem cells which include embryonic stem cells and adult stem cells. Stem cell transplantation is a transplantation technique which has involved in keeping healthy stem cells by removing unhealthy ones. The top open access journals are peer reviewed scholarly journals of transplantation. There are different types of stem cell transplantations which includes, autologous, allogeneic and syngeneic. Stem cell transplantation which involves the use of cells from same body known as autologous stem cell transplantation, Stem cell transplantation which involves the use of cells from donor called allogeneic stem cell transplantation and which involves the use of cells from an identical twin called syngeneic stem cell transplantation.