BACKGROUND The global prevalence of chronic noncommunicable diseases (NCDs) is on the rise, with the majority of the growth occurring among populations in developing countries. Few studies have quantified the health benefits for physical activity among sub-Saharan African adults. We examined associations of physical activity with the prevalence of metabolic syndrome (MetS) and its components in Ethiopian men and women. METHODS This cross-sectional study of 1,843 individuals (1,117 men and 726 women) was conducted among working adults (public schools and bank employees) in Addis Ababa, Ethiopia. The study was conducted in accordance with the STEPwise approach of the World Health Organization. Physical activity was assessed using a previously validated Global Physical Activity Questionnaire. MetS was defined according to the International Diabetes Federation criteria. Multivariable logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CI). RESULTS The odds of MetS was inversely associated with physical activity in men (P trend = 0.02) but not women (P trend = 0.85). Among men, the OR of MetS comparing those with high vs. low levels of physical activity was 0.56 (95% CI = 0.33-0.97). For women, the corresponding OR was 1.07 (95% CI = 0.57-2.01). Physical activity was significantly and inversely associated with high waist circumference and hypertriglyceridemia among men, but no such associations were observed among women. CONCLUSIONS Higher levels of physical activity were inversely associated with MetS and several individual components among men. No similar trends were observed among women in this cohort, in part because of the small sample size.