Many studies have shown that uric acid was related to hypertension. However, the association dependence on body mass index (BMI) or age was unclear. This study was performed with a group of 4012 Chinese population aged 30 to 92 years old. Subjects were divided into four groups according to the quartiles of uric acid (UA) concentration [First group: <= 231 mu mol/L (reference), Second group: 231-289 mu mol/L, Third group: 289-362 mu mol/L, Fourth group: > 362 mu mol/L]. Hypertension was defined as newly measured blood pressure >= 140/90 mmHg or taking antihypertensive drugs. Stratified analysis based on BMI (< 28 kg/m(2)vs >= 28 kg/m(2)) and age (< 60 years old vs >= 60 years old) to analyze the association between UA and hypertension. Subjects were 54.50 (45.00, 63.00) years old, and 40.98% were male, 38.33% were hypertension. Adjusted odds ratios (95% confidence intervals) for the association of UA and hypertension were 2.226 (1.662, 2.980), 4.340 (3.253, 5.790), 5.898 (4.434, 7.845) and 6.557 (4.927, 8.727) in the four groups among >= 60 years old respectively comparing with first group among < 60 years old. Adjusted odds ratios (95% confidence intervals) for the association between UA and hypertension were 2.170 (1.236, 3.808), 5.260 (3.267, 8.468), 9.056 (5.509, 14.888) and 3.730 (2.529, 5.550) in the four groups among BMI >= 28 kg/m(2)respectively comparing with first group among BMI < 28 kg/m(2). Uric acid was significantly associated with the hypertension. The association was stronger among subjects >= 60 years old or BMI >= 28 kg/m(2).