Endothelial progenitor cells (EPC) caracterized by the CD133+ marker contribute to neovascularization. Increasing EPC number in vitro could be a promising therapeutic tool. Human umbilical cord blood maintains a significant number of EPCs, suggesting the possibility of using these cells to induce revascularization of ischemic tissues. The aim of this study was to analyze the in-vitro function of differentiated CD133+ cells. As method has that, Cells were characterized by flow cytometry; VEGF mRNA expression was evaluated by RT-PCR analysis and the functionally by essays of capillary tubes formation. It resulted that, differentiated cells lost EPC markers, maintained low levels of markers for hematopoietic and monocytic cell lines and increased the expression of adult endothelial cell markers. Differentiated cells expressed VEGF mRNA and were capable to induce in vitro capillary tubules formation. Then it concluded that, CD133+ cells differentiated into endothelial cells in vitro are functionally active initiating the possibility of their use in future therapeutic applications.