Small-diameter vascular grafts are potential substitutes for damaged vessels in patients, but most biodegradable grafts available now are not strong enough. The present study examined the burst strength, radial compliance, suture retention strength for a novel biodegradable tubular scaffold and investigated its behavior in vivo. The tubular scaffold (6-mm i.d., 4 cm long) has three layers including porous polylacticglycolic- acid in both inner and outer layers, a compact polyurethanes layer in midst. Bone marrow stromal cells (bMSCs) were seeded on the scaffolds and cultured for 7 days in vitro to construct tissue engineered vascular grafts which were then implanted in canine abdominal aorta. After 1, 3, 6, 12 and 24 weeks, the grafts were retrieved and evaluated histologically, angiographically and immunohistochemically. The biodegradable tubular scaffolds showed wall thickness of 0.295 mm to 0.432 mm; radial compliance of 3.80%/100 mmHg similar to 0.57%/100 mmHg, burst strength of 160 kPa similar to 183 kPa, and suture retention strength of 1959 N/cm(2) similar to 3228 N/cm(2). The implanted grafts were fully patent without any signs of dilation or obstruction after 3 months' implantation. Scanning electron microscopy revealed a confluence endothelial cell layer spreading, on the inner surface of the grafts. Immunohistochemistry of the; retrieved grafts showed that vWF-stainin, alpha SMA-staining were positive in the inner and medium layer respectively. Masson's trichrome staining showed that amount of collagen fibers existed in the grafts wall. Overall, these novel three-layered scaffolds exhibited favourable mechanical strength, long term patency and good remodeling in vivo.