Abstract: Purpose: The objective of this pilot study was to establish an animal model for intra-abdominal infection and to examine the effect of sildenafil on anastomotic healing of the left colon and intra-abdominal adhesion formation. Methods: Fourteen Winstar rats underwent colonic transsection and primary anastomosis after performing intra-abdominal infection. Rats were divided into two groups: Group 1 (n = 7): intra-abdominal infection, resection, and anastomoses; Group 2 (n = 7): intra-abdominal infection, resection, anastomoses, and sildenafil. Anastomotic bursting pressures, hydroxyproline levels, histopathologic grading, and abdominal adhesions were accessed on the postoperative Day 7. Results: Anastomotic healing was found to be improved in terms of a bursting pressure (P = 0.02). Histopathological examination revealed an increase in angiogenesis (P = 0.007). Moreover, intra-abdominal adhesions were significantly less in rats given sildenafil (P = 0.03). Conclusion: Sildenafil may improve anastomotic healing of the left colon and diminishes peritoneal adhesion formation in the presense of abdominal infection.