Abstract: Recent progress in research on stem cells has more clearly revealed the roles and mechanisms of stem cells in the treatment of cardiac diseases. Thanks to their cardiac specificity and committed differentiation potential, cardiac stem cells (CSCs) have more advantages than other types of stem cells in treatment of cardiac diseases. CSCs can be divided into different groups according to the markers they express. This review introduces the phenotypic characteristics, differentiation potential and clinical application of different cardiac stem cells. In particular, the review focuses on the effects of hostile environment of air and space such as hypoxia and radiation on cardiac stem cells.