Cell-based therapy has emerged as a promising solution in the field of medicine by exploiting the inherent properties of living cells. This therapy has great potential for regenerative medicine, particularly in developing new strategies for cancer treatment. This chapter provides a comprehensive overview of cell-based therapy development from the early stages to the present. At the same time, some types of cell-based therapies, such as stem cell therapies and mature differentiated cell therapies, have been described. Furthermore, the potential applications of this technology in the future are discussed. In addition, the rapid development of the therapy has also brought with it ethical and other issues. Therefore, the most prominent issues existing in the therapy have been mentioned. In summary, this chapter provides useful information for scientists, physicians, and patients about the importance, potential, and development direction of the therapy. This evidence can be used as a starting point for further research directions for each specific cell therapy.