Objectives: To evaluat the possibility of decellularized valved conduit, we performed in vivo animal experiment using porcine valve and analysed functional and histological characteristics. Methods: Porcine aortic valves were decellularized with Triton treatment. After decellularization, scaffolds were implanted to right ventricular outflow tract of another porcine. And we rerieved implanted decellularized valves at 3 week, 4 week, 5 month and 7 month. Retrieved valves were analysed usiung histological staining and immunohistochemical staining. Results: Valve leaflet of retrieved implants from right ventricular outflow tract showed normal mprphology at 4 week and 5 month. But, among 2 animals, the leaflets were destroyed and calcified due to infection. And leaflet motion was normal in not infected valve leaflet at 5 month. Conduit portion was well endothelialized by migration of endothelial cell from adjacent native vessel. Histological examination showed well endothelialized conduit luminal surface. And smooth muscle layer was also regenerated from adjacent vessel but the array was irreugular. And regeneration was locallized about 1.5 cm from suture line. Conclusions: It is possible to use decellularized porcine aortic valve in pulmonary valve portion. But, cellular regeneration was incomplete. Autologous cell seeding may solve this problem.