Objectives: to detect the clinical and echocardiographic parameters that predict AF in coronary artery disease (CAD) patients after coronary artery bypass surgery (CABG). Methods: one hundred CAD patients scheduled for CABG were included. Standard 2D, PW Doppler and 2D speckle tracking echocardiography were performed to assess left atrial (LA) and ventricular (LV) function and their role in predicting post-operative atrial fibrillation (POAF). Results: twenty-two percent of patients developed POAF. POAF patients were significantly older (P= 0.001) with increased heart rate (P= 0.001). POAF patients had increased LA diameters and volumes (P < 0.001). Left ventricular ejection fraction (LVEF) was significantly lower in POAF patients (P < 0.004). POAF patients had significantly lower LA and LV global longitudinal strain (LVGLS) (p < 0.001). Clinical predictors of POAF were age and heart rate (P < 0.001). While, echocardiographic measures associated with POAF were LA and LV global longitudinal strain (P <0.001). LA longitudinal strain ≤ 23.1 (85% sensitivity and 66% specificity ) and LVGLS ≤ -14.4 (70% sensitivity and 85% specificity) predicted POAF. Conclusion: Preoperative LA and LV global longitudinal strain predicts POAF in CABG patients. Echocardiographic deformation measures can enhance clinical profile to identify patients at high risk for POAF.