Background: Epicardial Adipose Tissue (EAT) is the cardiac visceral adipose tissue, influencing its structure and function, and easily assessed by trans-thoracic echocardiography. Vitamin D deficiency is prevalent among obese adolescents and is thought to affect the cardiovascular system. Objective: This study was aimed to assess the EAT thickness (EATT) and Vitamin D status in obese adolescents to clarify their relationship with cardiovascular dysfunctions. Patients and Methods: This was a case-control study done at the Internal Medicine Outpatient Clinics of Al-Azhar University Hospitals during the period from February 2016 to February 2018. It included 90 ado lescents divided into two equal groups; obese group (45 obese) and healthy non-obese group (45 ones). Hi story taking, clinical examination, laboratory investigations, and echocardiographic assessment were done to retrieve all relevant data. Results: Obese adolescents were substantially different from non-obese regarding their anthropometrics w ith worse glucose homeostasis, insulin resistance and lipid profile, with a high prevalence of Metabolic Sy ndrome (MetS) (57.8%). Echocardiographically, they had a significantly increased carotid intima-media th ickness (cIMT) and EATT, higher incidence of hypertrophic cardiac remodeling, impaired systolic and dia stolic LV and RV functions. 25-Hydroxy Vitamin D (25[OH]VD) levels was lower in obese group vs. non -obese (10.2 ± 3.8 vs. 19.09 ± 7.8) respectively. EATT, cIMT, and s. Adiponectin showed the highest diag nostic capability in identification of Adolescence obesity and MetS. Conclusion: EATT is an easily obtainable marker of cardiovascular structural and functional derangements. Vitamin D deficiency significantly worsen the cardio-metabolic risk profile and the cardiovascular function among Egyptians obese adolescents.