Objective: We sought to assess the left ventricular functionbefore an after coronary artery bypass graftingBackground: After coronary artery bypass, it is important to clearly assessresidual ischemia and ventricular ejection fraction , as it has been describedas a prognostic value in patients with coronary artery bypass graft. It is wellrecognized that surgical revascularization improves left ventricularfunctions in patients with coronary artery disease. Echocardiographicevaluation before and after coronary artery by bass grafting is a noninvasive technique that provides quantitative analysis of regionalmyocardial function , systolic and diastolic function .Methods: We studied 30 patients off-pump and 10 patients on-pump .echocardiography was performed one week before CABG and 1 month ,2months and 3 months after CABG. The follwing parameters weremeasured at the apical 4-chamber view : Left ventricular End diastolicdiameter (LVEDD); Left ventricular End systolic diameter (LVESD); Leftventricular Ejection fraction (LVEF); Let ventricular diastolic function (bypulsed tissue Doppler).Results: Echocardiographic study of LV function showed that significantimprovement in ejection fraction after one week of CABG 59.6 ± 4.3 versus52.9 ± 6.3before CABG P < 0.05 (significant difference) which persisted significantlyat different follow up periods. TDI showed that significant improvement in Emvelocity , Em/Am ratio post operative CABG 71.4 ± 7.7 ; 1.55 ± 0.3 versus 64.8 ± 9.7;1.3 ± 0.4 before CABG respectively P < 0.05 (significant difference).Comparison between two groups (off pump and on pump CABG ) showedthat significant differences regarding post operative complicationsaccording to Days on mechanical ventilation (> 24 hours) 1 (10%) versus 5(16.7%) respectively P < 0.05 (significant difference) . according to Overallcomplications 4 (40%) versus 16 (53.3%) respectively P < 0.05 (significantdifference)Conclusion: Echocardiography showed marked improvement in systolicLV functions. TDI showed that marked improvement in LV diastolicfunction.