Objective: Endothelial progenitor cells are very important for the study of anti-angiogenic therapy. We tried to obtain endothelial progenitor cells from cord blood and studied their biological characteristics. Methods: The mononuclear cells were isolated from cord blood and adult human peripheral blood and then induced to differentiate into endothelial cells in vitro. Morphological characteristics were studied under a phase-contrast microscope and determined by immunohistochemistry. The properties of these two kinds of different origin cells were compared. Results: More endothelial progenitor cells were obtained from cord blood than from the same volume of human peripheral blood. In addition, a greater number of adherent cells and cell clusters developed from a similar number of mononuclear cells from cord blood than from adult peripheral blood. Both kinds of cells began to express several kinds of endothelial markers after seven days’ primary planting. The number and proportion of the cells that expressed endothelial markers increased with the time of culture. Under the culture conditions used in this study, no cells proliferated. Conclusions: A great number of endothelial progenitor cells exist in cord blood. These cells derived from cord blood have the same biological characteristics as their counterparts from adult peripheral blood. They provide a promising source for in vivo studies of tumor anti-angiogenic therapy.