Background: Glycated hemoglobin values reflect two to three months average endogenous exposure to glucose including postprandial spikes in blood glucose level and have low intra-individual variability particularly in non-diabetic patients. Elevated hemoglobin A1C is regarded as an independent risk factor for CAD in patients with or without DM, The purpose of this study is to determine the correlation between the level of Glycated hemoglobin (HbA1c), and the severity of coronary artery disease in non-diabetic patients.Study design and methods: The study included four hundred and eight patients referred to coronary angiography in two tertiary centers. All patients were subjected to complete medical history, physical examination and full labs including HbA1c. Transthoracic echocardiogram and coronary angiography were done and the Gensini score was calculated.Normally distributed continuous variables will be represented as mean ±SD, or as the percentage of the sample. Comparison between high and low risk groups was done using two-tailed unpaired student t test for continuous variables and the Pearson's chi-square test for categorical variables.Results: two hundred and ninety two patients (71.6%) high risk group and 28.4% were low risk group. High risk group had HbA1c (HbA1c 5.7 – 6.4%) mg% with mean HbA1c of 6.1± 0.3.The mean Gensini score was 39.9± 34.9. The level of HbA1c was positively correlated with Gensini score (r=0.243, P<0.05,) and RWMSI (r=0.103, p=0.038) and negatively correlated with LVEF(r= -0.146, p=0.003).