BACKGROUND: In many studies, obesity is highly correlated with adverse coronary risk profile. Increased left ventricular (LV) mass is an independent risk factor for cardiovascular mortality and morbidity. Hypertension is an well known factor related with LV mass. Obesity also is related with LV mass and commonly associated with hypertension. However, few data are available concerning the relations of LV mass to central obesity, especially in Korean hypertensive patients. So, this study was to evaluate the significance of waist circumference in determinants of LV mass in Korean hypertensive patients. METHODS: A total of 74 hypertensive [40 women, 34 men; mean age, 62.5 years; mean body mass index (BMI), 25.0 kg/m2, 17 with type 2 diabetes] patients without prevalent cardiovascular disease were studied. Echocardiographic LV septal thickness, LV posterior wall thickness, LV dimension and LV mass were analysed. RESULTS: LV mass, diastolic left ventricular internal dimension and epicardial fat thickness were larger in men than in female. LV mass was larger in obese patients defined by body mass index and also in central obese patients defined by waist circumference. LV mass was correlated with sex, body mass index, waist circumference, diastolic left ventricular internal dimension, left ventricular posterior wall thickness and interventricular septal thickness. After controlling for age, sex and body mass index, waist circumference was correlated with LV posterior wall thickness and LV mass. CONCLUSION: Waist circumference may be more important than BMI in determinants of left ventricular mass in Korean hypertensive patients.