SUMMARY OBJECTIVE: Hot flashes have a negative impact on the quality of life of women during the menopausal transition and thereafter. The progressive reduction in gonadal estrogen levels associated with aging promotes an accumulation of abdominal fat, dyslipidemia, and arterial hypertension, all of which are components of metabolic syndrome (MetS). The objective of the present study was to estimate the prevalence of hot flashes and evaluate their relationship with MetS in women ≥ 40 years of age. METHODS: This was a cross-sectional study involving women aged between 40 and 65 years. We used the Kupperman index to quantify the climacteric symptoms and the National Cholesterol Education Program Adult Treatment Panel III criteria for the diagnosis of MetS. RESULTS: 1,435 women were initially selected, and we obtained information from 647. The mean age at menopause was 45.99 years (SD 6.61 years) and the prevalence of hot flashes and MetS were 55.83% (95% CI: 52.35-59.25%) and 46.29% (95% CI: 44.75-52.53%), respectively. We identified a positive association between MetS and hot flashes (OR 1.16; 95% CI: 1.01-1.33). CONCLUSIONS: In women ≥ 40 years of age, hot flashes are highly prevalent and appear to be associated with MetS.