Background: Anastomotic leak is regarded as one of the most feared complications of bowel surgery; avoiding leaks is a major priority. Attempts to reduce or eliminate leaks have included alternate anastomotic techniques. Human oral mucosa stem cells (hOMSC) are self-renewing and expandable cells derived from buccal mucosa. Studies have shown that hOMSC can accelerate tissue regeneration and wound healing. The objective of this study was to evaluate whether hOMSC can decrease anastomotic leak rates in a murine model of colon surgery. Methods: Two experiments were performed. In the first study, mice underwent colonic anastomosis using five interrupted sutures. hOMSC (n = 7) or normal saline (NS; n = 17) was injected into the colon wall at the site of the anastomosis. To evaluate whether hOMSC can impact anastomotic healing, the model was stressed by repeating the first experiment, reducing the number of sutures used for the construction of the anastomosis from five to four. Either hOMSC (n = 8) or NS (n = 20) was injected at the anastomosis. All mice that survived were sacrificed on postoperative day 7. Anastomotic leak rate, mortality, daily weight, and daily wellness scores were compared. Results: In the five-suture anastomosis, there were no differences in anastomotic leak rate, mortality, or daily weight. Mice that received hOMSC had significantly higher wellness scores on postoperative day 2 (p < 0.05). In the four-suture anastomosis, there was a significant decrease in leak rate (70% [NS] vs. 25% [hOMSC], p = 0.029) and higher wellness scores in mice that received hOMSC (p < 0.05). Conclusion: Our study suggests that injecting hOMSC at the colonic anastomosis can potentially reduce anastomotic leak and improve postoperative wellness in a murine model of colon surgery.