Abstract: Objective To investigate the endothelial function of artery and the related factors in the elderly patients with both essential hypertension and abdominal obesity. Methods A total of 658 elderly patients（≥60 years old） with essential hypertension and 64 elderly subjects without clinical evidence of hypertension were recruited from the department of geriatrics and the department of general medicine from August 2000 to May 2016. The dilatation of anterior tibial artery induced by reactive hyperemia was examined by high-resolution vascular ultrasound, and was then defined as endothelium-dependent dilatation（EDD）. All the participants were divided into four groups based on blood pressure（≥140/90 mm Hg was defined as hypertension） and waist circumference（male≥90, female≥85 cm was defined as abdominal obesity）: normotensive without abdominal obestiy, normotensive with abdominal obesity, hypertensive without abdominal obesity, hypertensive with abdominal obesity. Pearson correlation analysis, factorial analysis and multiple linear regression analysis were undertaken to examine the related factors of EDD. Results Factorial analysis showed that hypertension and abodominal obesity were influence factors of EDD, but there are no interaction between them. From normotensive without abdominal obestiy, normotensive with abdominal obesity, hypertensive without abdominal obesity, to hypertensive with abdominal obesity, a gradual decline in EDD was observed （9.37±1.11）% vs（8.59±0.99）% vs（7.70±0.30）% vs（6.75±0.26）%, P＜0.05. In elderly hypertensive patients with abdominal obesity, EDD correlated with waist circumference（r=-0.139, P＜0.05）, systolic blood pressure（r=-0.245, P＜0.05）, pulse pressure（r=-0.287, P＜0.05）, fasting glucose level（r=-0.131, P＜0.05）. Multivariate linear regression analysis revealed that EDD was associated with pulse pressure（β=-0.280, P＜0.001） and waist circumference（β=-0.141, P=0.009）. Conclusion In elderly patients with essential hypertension and central obesity, EDD is impaired, and it is negatively correlated with pulse pressure and waist circumference.