To estimate the prevalence of overweight and obesity and factors associated. The study analyzed data referring to individuals aged 18 years or older interviewed through the system Vigilância de Fatores de Risco e Proteção para Doenças Crônicas por Inquérito Telefônico (VIGITEL--Telephone-based surveillance of risk and protective factors for chronic diseases), carried out in the Brazilian capitals and Federal District in 2006. For 49,395 individuals, the body mass index (BMI) was used to identify overweight (BMI > or = 25 kg/m2) and obesity (BMI > or = 30 kg/m2). Prevalence and prevalence ratios were presented according to sociodemographic variables, level of schooling, health condition/comorbidities, and self-evaluation of health, stratified by sex. Poisson regression was employed for crude and age-adjusted analyses. The prevalence of overweight was of 47% for men and 39% for women, obesity was around 11% for both sexes. Direct association was observed between overweight and level of schooling among men and inverse association among women. Obesity was more frequent among men living with a partner and was associated neither with level of schooling nor skin color. The prevalence of overweight and obesity was higher among black women and women who lived with a partner. The presence of diabetes, systemic arterial hypertension and dyslipidemias, as well as the subject perceiving his/her health as regular or poor, were also reported by the interviewees with overweight or obesity. While approximately one out of every two interviewees was classified as being overweight, obesity was reported by one out of every ten interviewed subjects. Socioeconomic and demographic variables, as well as reported morbidities, were associated with overweight and obesity. These results were similar to the ones found in other Brazilian studies.