Background: The degree of degenerative aortic valve disease (DAVD) can play a significant role as an independent risk factor for coronary artery disease. Therefore, it can be directly linked to coronary artery disease (CAD) severity making its assessment and measurement a critical step before the invasive investigations to diagnose CAD. Objective: The present work aimed to assess the relationship between DAVD by transthoracic echocardiography (TTE) on the aortic valve, and the severity and complexity of coronary artery disease assessed by SYNTAX score. Patients and Methods: This prospective study included 100 patients with Echocardiographic evidence of DAVD, and risk of coronary artery disease indicated for coronary angiography at Al-Azhar University (Assiut branch) between November 2020 to December 2021. Informed consent, detailed history, complete physical examination, resting ECG, full labs, complete transthoracic echocardiographic examination, particular emphasis on degenerative aortic valve assessment, and coronary angiography were performed. Assessment of severity of CAD was done for all patients using SYNTAX score, number of affected vessels, and degree of stenosis were also assessed. Results: There were a statistically significant positive strong correlation between DAVD degree with both SYNTAX score and number of affected vessels. Conclusion: Aortic valve sclerosis, calcification, and degeneration were strongly correlated with the extent of coronary artery disease and may predict it. Echocardiographic detection of DAVD in patients undergoing coronary angiography could be applied as a new surrogate marker of the extent of coronary atherosclerosis. DAVD was associated with atherosclerosis risk factors like age, dyslipidemia, DM, and hypertension.