In developed countries in the West, lower socioeconomic status (SES) is associated with a higher prevalence of overweight/obesity. The authors examined the association between SES defined by education and income and overweight/obesity in a population-based cohort of 2807 individuals of Malay ethnicity (age 40-80 years, 51% women) in Singapore. The prevalence of overweight/ obesity (body mass index > or =25 kg/m(2)) in men and women was 50.4% and 65.1%, respectively. In women, the prevalence of overweight/obesity increased with lower levels of education and income. Compared with the higher categories of SES, the odds ratio (95% confidence interval) of overweight/obesity in women was 1.42 (1.06-1.89) for education and 2.08 (1.33-3.26) for income. In contrast, in men, the prevalence of overweight/obesity decreased with lower levels of education and income (P interaction by gender <.05 for all SES variables). Lower SES was positively associated with overweight/obesity in Malay women, and the association was in the opposite direction in Malay men.