Background: To describe overall physical activity prevalence measured by the Global Physical Activity Questionnaire as well as inequalities in leisure-time physical activity among Brazilian adults (15 y and older). Methods: Data from the Brazilian Survey on Medicine Access, Utilization, and Rational Use of Medicines were analyzed. The study was carried out between September 2013 and February 2014. Physical activity was measured through Global Physical Activity Questionnaire and classified according to the recommendations of the World Health Organization. Additional analysis determined the contribution of each physical activity domain to the total amount of physical activity. Inequalities in terms of sex, age, and socioeconomic position were explored. Results: About one-third of the participants (37.1%; 95% confidence interval, 35.5–38.8) were physically inactive. Work-based activities were responsible for 75.7% of the overall physical activity. The prevalence of participants achieving physical activity guidelines considering only leisure-time activities was 17.8% (95% confidence interval, 16.7–19.2). Females and older participants were less active than their counterparts for both overall and leisure-time physical activity; socioeconomic status was positively associated to leisure-time physical activity. Conclusions: Major overall physical activity is attributed to work-related physical activity. Leisure-time physical activity, a key domain for public health, presents important gender and socioeconomic inequalities.