The objective of this study was to evaluate the correlation of serosal patching in dogs with existing septic peritonitis with continued postoperative septic peritonitis and death. Records were collected from dogs that underwent intestinal surgery from 1998 to 2007 at four veterinary teaching hospitals and one private referral clinic. Dogs were included if they were diagnosed with septic peritonitis and had subsequent surgery of either the small intestine or cecum. Eighty-two surgeries were evaluated. Eighteen dogs (22%) received a serosal patch during surgery. Of those, three dogs (16.7%) had septic peritonitis postoperatively. Sixty-four dogs (78%) did not receive a serosal patch, and 19 of those dogs (29.7%) had postoperative septic peritonitis (P = 0.27). Of the 18 cases with serosal patching, 6 (33.3%) died prior to discharge. Of the 63 cases that did not receive a patch and had information regarding survival, 14 (22.2%) died prior to discharge (P = 0.34). Use of a serosal patch did not protect dogs from either postoperative septic peritonitis or failure to survive.