Although cardiovascular events occur more frequently among patients with metabolic syndrome (MS) or diabetes mellitus (DM), the impact of gender is unclear. We aimed to determine the relation of MS and DM on cardiovascular events between men and women. The National Health Survey of 1992 provided information on outcomes for 3,414 Singaporeans aged 18 to 69 years without cardiovascular diseases. Definition of MS was based on the National Cholesterol Education Program criteria. Cardiovascular events included hospital admissions for coronary heart disease, stroke, and cardiovascular mortality. The proportion of subjects with MS was 12.4%. After 10 years, the annual cardiovascular event rates (per 1,000 person-years) for men without DM were 3.0 and 15.9 among subjects without and with MS, respectively, and the respective rates for men with DM were 22.5 and 21.4. The corresponding rates for women were 0.9, 3.7, 5.3, and 21.5, respectively. Among nondiabetic subjects, cardiovascular events occurred more frequently among men than women among subjects with MS (adjusted hazard ratios [HRs] 4.71, 95% confidence interval [CI] 1.56 to 14.2) and those without MS (HR 3.35, 95% CI 1.78 to 6.31). Among patients with DM, cardiovascular events occurred more commonly among men than women without MS (HR 6.04, 95% CI 1.43 to 25.6). Rates for cardiovascular events were comparable between men and women with DM and MS (HR 0.98, 95% CI 0.48 to 1.99). In conclusion, the adverse impact of MS or DM was greater among men, and the presence of both conditions increases the risk substantially for cardiovascular events among women.