We examined blood pressure (BP) in association with weight change since age 20, body mass index (BMI) at different ages and fat distribution in normotensive individuals using baseline survey data collected in the Shanghai Men's Health Study, an ongoing population-based prospective cohort study of Chinese men aged 40-74 years. All anthropometric and BP measurements were performed by medical professionals. Included in this analysis were 25 619 men who had no prior history of hypertension, diabetes or cardiovascular disease, never took any antihypertensive medication and had both normal systolic BP (SBP) and diastolic BP (DBP) (<140/90 mm Hg). Both SBP and DBP increased linearly across the whole range of weight gain since age 20. The adjusted mean differences between the highest and the lowest quintiles of weight gain were 6.0 mm Hg (95% confidence interval (CI): 5.6, 6.5) for SBP and 3.9 (95% CI: 3.6, 4.2) for DBP. When accounting for BMI at age 20, the multivariate-adjusted odds ratio of prehypertension (SBP, 120-139 and/or DBP, 80-89 mm Hg) was 4.1 (95% CI: 3.7, 4.5; P for trend <0.0001) comparing the extreme quintiles of weight gain. Similar positive associations were also observed for BMI at age 40, current BMI, circumferences of the waist and hips and waist-to-hip ratio. In conclusion, these data suggest that weight gain since age 20 and elevated adiposity may contribute significantly to the rise in BP in normotensive individuals, emphasizing the importance of weight control throughout adulthood in preventing high BP.