Introduction: A diabetic oral ulcer is a lesion caused by increased Advanced Glycosylation End Products (AGEs). AGEs increase intracellular expression of ROS, NFκB and COX-2 which prolong ulcer healing time. The propolis extract gel has an antiinflammatory effect thus decreased the expression of NFκB and COX-2. Methods: This was an original experimental research design featuring post test-only control groups. Mice were induced by Streptozotocin at dose 50mg/kg body weight. Twenty seven male mice were distributed equally into 3 experimental groups which are : non-diabetic control mice; diabetic mice and diabetic mice treated daily with a topical application of propolis. Propolis extract gel application is done every day, 3 times a day with a time span of 6-8 hours up to the day specified for tissue removal, days 1, 3, and 5. The treated diabetic mice were then sacrificed, then the expression of NFκB and COX-2 in the labial mucosal epithelium was assessed by doing immunohistochemistry. The expression of NFκB and COX-2 was observed on day 1, 3, and 5 with monoclonal antibodies NFκB (Santa Cruz Biotechnology, Inc, sc-8008) and monoclonal antibodies COX-2 (Santa Cruz Biotechnology, Inc, sc-1747). Results: Propolis extract gel decrease the expression of NFκB and COX-2 in the treatment group on day 1, 3 and 5. Conclusion: Propolis extract gel proven to have an effect as an antiinflammatory in diabetic oral ulcer healing in Streptozotocin-Induced Type I Diabetic Mouse Model.