Objectives:In congenital heart defect corrective surgery, the commonly used prosthetic replacement grafts limited durability and often require repeat operations because of their lack of growth potential. Using the child’s own stem cells to produce tissue engineered vascular grafts may provide better grafts for surgery. Here we set out to investigate stem cells isolated from umbilical cord blood that can produce sufficient functional endothelial cells (ECs) and vascular smooth muscle cells (SMCs) for tissue engineering autologous vascular grafts. Methods Human endothelial progenitor cells (EPCs) and mesenchymal stem cells (MSCs) were isolated from umbilical cord blood (UCB) by density gradient centrifugation and culturing in selective media. UCB-EPCs were characterized by their surface markers and EC functional assay (capillary formation assay). UCB-MSCs were fully characterized by their cell surface markers and multipotency. The SMC differentiation was induced by the growth factor TGF-β1 and analysed by immune-histological, flow cytometry and molecular biological methods. Those cells were applied in vascular tissue engineering by seeding on a decellularized scaffold (CorMatrix ECM) using a hollow organ bioreactor in vitro. Pig was selected for the in vivo test. Newborn piglet peripheral blood derived MSCs were harvested and tested for vascular tissue engineering by similar methodology. Results:In vitro expanded and differentiated UCB-EPCs displayed matured EC phenotypes & EC surface makers and were capable to form capillary-like structures when plated with the BD matrigel support. UCB-MSCs expressed typical MSC surface markers. Their multipotency was approved by their adipogenic and osteogenic differentiation capability. After incubated in SMC differentiation medium for a period of 8-12 days, histological and molecular analyses showed a consist expression of SMC-related markers. Those matured cells had satisfactory survival rate and proliferative ability when seeded on the CorMatrix ECM. The histological staining showed that SMCs were able to form a multi-cells layer on the scaffold. The pig peripheral blood derived MSCs showed similar multipotency, include the smooth muscle cell differentiation potential, and the potential in vascular tissue engineering. Conclusions: Our investigation suggests that, readily available perinatal tissue, like umbilical cord blood provides good stem cell sources to use in vascular graft tissue engineering for paediatric surgery. Those stem cells are capable to produce a live vascular graft when seeded onto a decellularized scaffold.