Background: Atrial fi brillation (AF) is the most common arrhythmia; at least more than two million individuals suffer from AF in the United States alone. AF is associated with high disease morbidity, mortality, a higher risk of stroke and thromboembolism. There are limited data on the role of Interleukin 6 (IL-6) as a prognostic factor in atrial fibrillation. So, we aimed to assess Interleukin 6(IL-6) level in AF subtypes and identify the relationship between IL 6 level, and short-term outcomes in AF. Results: Our results included three groups paroxysmal AF (19 cases), persistent AF (19 cases), and 19 in the control group; IL-6 level had the highest mean value in persistent AF at admission, after 24 h and after 7 days.13patients(68.4%) patients with paroxysmal AF experienced normal sinus rhythm and 6 patients (31.6%) developed ischemic stroke .4 cases(66.66%) from a total of 6 patients developed stroke after 24h while 2 cases (33.33%) developed stroke after 7 days. IL-6 level at admission was significantly related to the occurrence of stroke (RR: 2.571, CI: 0.5-1.1, p :0.002 ), and also at 24h (RR:2.267, CI: 2.267 (0.4-1.21), p: 0.0374). IL-6 equal to or more than 6.6 pg/ml was a statistically significant predictor of stroke occurrence with a sensitivity of 84.4%, and specificity of 66.7%P: 0.001. Conclusions: PlasmaIL-6 level was associated with the initiation and perpetuation of AF, and also was associated with the prognosis of AF. Admission of IL-6 at a cutoff value ≥ 6.6 pg/ml was a predictor of stroke occurrence in paroxysmal AF patients. Keywords: Atrial fibrillation; Interleukin 6; Stroke