It is has been established that endothelial progenitor cells EPC are of great interest in the maintenance of endothelial integrity and postnatal neovascularization of the adult organism’s tissues. It is shown that the formation of new blood vessels can be carried out both by angiogenesis and vasculogenesis from EPC. In this review, data are presented on the heterogeneity of the EPC in population. These cells are indentified by different markers and have different proliferative and functional capacities. They not only activate the neovascularization of tissues after damage, but also they are potential candidates for therapeutic angiogenesis.