Introduction: Anastomotic leak is a dreaded complication following gastrointestinal (GI) anastomotic surgery. It increases the morbidity and mortality of patients undergoing GI surgery. However, there is a paucity of data on the incidence and risk factors of anastomotic leak following gastrointestinal surgery in Uganda. The main objective of this study was to determine the incidence and risk factors of anastomotic leak following gastrointestinal surgery in Mulago Hospital, between April 2024 and July 2024. Methods: We consecutively recruited adult patients admitted to the general surgery wards in Mulago Hospital, 24 hours following gastrointestinal surgery. Patient-related factors including preoperative anemia, preoperative albumin level, and ASA status were recorded on entry, while the outcome (anastomotic leak) was obtained upon 14 days follow-up. Data were analyzed using SPSS version 26. Multivariate logistic regression was used to determine the independent risk factors for anastomotic leak, p< 0.05 was considered statistically significant. Results: Eighty-five participants were studied. The incidence of anastomotic leak was 8.2% (n=7). Hemoglobin level of less than 10 g/dl was the only independent predictor for an anastomotic leak in this study. (RR, 8.15; 95% C.I, 1.16 - 57.48; p=0.035). Conclusion: The incidence of anastomotic leak in Mulago National Referral Hospital was low. Low Hemoglobin (Hb<10g/dl) was associated with increased anastomotic leak rates. Keywords: Anastomotic leak, Gastrointestinal Surgery, Incidence.