Anastomotic leakage after colonic resection still remains a troublesome complication of major clinical significance. Systemic (nutritional status, blood viscosity) or local factors (contamination by local germs, suture technique) seems to be implicated in the healing process of the suture line. The CO2 laser as a cutting procedure in colonic resection should provide a useful tool for its accuracy and the bactericidal properties. We have tested the strength of an end-to-end anastomosis of rat colon resected by CO2 laser, scalpel and diathermy, respectively, by measuring the bursting pressures at different postoperative days. The present study shows that the use of CO2 laser resulted in a significant increase of colonic bursting pressure at the anastomotic site.