Objective: To evaluate the feasibility and results of using serosal patch of small bowel for repair and replacement of inferior vena cava (IVC) after resection of a part of infra-renal IVC in an animal model, as it may be encountered in extensive tumors of retroperitoneal and trauma patients.Methods: Five healthy sheep of both sexes were prepared. After general anesthesia and laparotomy, a defect with 1 cm width and 4cm length was made on anterior aspect of infra-renal IVC, and then an adjacent loop of small bowel was brought and sutured continuously to cover the defect of IVC as a patch graft. The observation period was two months.Results: Three of five IVCs were macroscopically patent without stenosis and thrombosis. Pathologic assay revealed complete endothelialization of serosal surface of the patch of small bowel loop. One of IVCs was completely occluded in gross evaluation and fibrous formation in pathologist review. The sheep had no sign of venous hypertension and edema of limbs. One sheep died at the night of first operation due to internal bleeding.Conclusion: Serosal patch of small bowel is an accessible and feasible alternative in repair and reconstruction of IVC especially when there is restriction for use of prosthetic material in a contaminated space of abdomen.