Objective To investigate the inttuenee of elevated fasting blood glucose(FBG)on left ventrieular ejection fraction(LVEF)after acute myocardial infarction(AMI).Methods The relationship between FBG(≥8-hour fast within 24 hours of admission)and LVEF in 161 patients with AMI was studied prospectively.Patients were grouped by FBG (group 1,FBG＜6.1 mmol/L,group 2,FBG 6.1-6.9mmol/L,group 3.FBG≥7.0mmol/L).LVEF was measured at admission and at 30 days after AMI onset Results Compared with that of normal FBG(group 1),LYEF of elevated FBG(group 2 and group 3)was lower[for admission:(49.3±6.7)%,(45.8±7.4)% vs (52.4±7.7)%,P＜0.05;for 30day8:(52.7±7.3)%,(49.2±7.2)% vs (55.8±7.4)%.P＜0.05].ConclusionElevated FBG is associated with worse LVEF after AMI.