Background: Rheumatic heart disease (RHD) combined with atrial fibrillation (AF) significantly contributes to thromboembolic complications, including ischemic stroke. The coexistence of these conditions increases the risk of cardiovascular issues, underscoring the need for targeted management strategies. Objective: This study aims to assess the prevalence and determinants of thromboembolic events among patients with RHD and AF at the Tikur Anbessa Specialized Hospital adult cardiac outpatient clinic in Addis Ababa, Ethiopia. Methods: An institution-based retrospective chart review of adult patients with RHD and AF was conducted. Data were gathered from electronic medical records using structured data extraction check list. Descriptive analysis using frequency with percentage and mean with standard deviation was conducted. Binary logistic regression was employed to analyze the relationship between predictor variables and thromboembolic events. Results: A total of 182 participants were included in this study. The mean age of participants was 40.37 (SD± 13.01) and majority of participants were female participants (70.9%). The overall rate of cardioembolic events was 19.78% (95% CI: 14.3-6.3), with stroke occurring in 18.1% (33) of the participants. Disease duration (AOR: 1.07, 95% CI: 1.03–1.13), left atrial size (AOR: 1.14, 95% CI: 1.07–1.24), presence of left atrial thrombus (AOR: 9.83, 95% CI: 1.53–63.21), mitral stenosis (AOR: 1.88, 95% CI: 1.21–17.14), and Subtheraputic INR levels (<2) (AOR: 4.27, 95% CI: 1.15–15.94) were significantly associated with cardioembolic events. Conclusion and recommendation: This study highlights the high prevalence of cardioembolic events in patients with RHD and AF, identifying both modifiable and non-modifiable factors that contribute to increased risk. Monitoring left atrial size and INR levels could help reduce the risk of thromboembolic complications. Further research is needed to develop preventive strategies and optimize management to improve patient outcomes.