Background: Coronary artery disease (CAD) is a group of diseases that includes stable angina, unstable angina, myocardial infarction and sudden cardiac death. It's the most commonly occurring type of cardiovascular diseases. Risk factors for CAD include hypertension, diabetes mellitus, smoking, alcohol ingestion, obesity, dyslipidemia, sedentary life and family history. The underlying mechanism involves atherosclerosis of the arteries of the heart Objectives: The aim of the work was to assess the prevalence and pattern of coronary artery disease through invasive coronary angiography in diabetic patients with cardiomyopathy. Patients and Methods: Fifty diabetic patient with echocardiographic evidence of cardiomyopathy were enrolled in this study, which conducted at Cardiology Department Azhar Assuit University Hospital during the period from November 2018 to March 2021. Informed consent was obtained from every patient after explanation of the procedure. Medical research and Ethics Committee approved the study. Results: As regard HbA1c there was highly statistically significant (p-value < 0.001) positive correlation (r = 0.82) between HbA1c and duration of DM. Highly statistically significant (p-value < 0.001) positive correlation between (HbA1c and SYNTAX score) and (duration and SYNTAX score). Conclusion: There was a correlation between HbA1c and SYNTAX score and duration of diabetes.