ObjectiveIn Morocco, the association between obesity/overweight and socio-demographic and lifestyle factors is poorly understood. The present study aimed to investigate this association in a representative sample of the Moroccan population aged 18 years and above.DesignThis is a cross-sectional study using a questionnaire including demographic, socio-economic and physical activity items. Height and weight were measured and BMI was computed. The association between obesity (BMI ≥ 30·0 kg/m2) or overweight (25·0 ≤ BMI < 29·9 kg/m2) and the other variables was analysed using multiple binomial logistic regression, separately in men and women.SettingThe whole Moroccan territory.SubjectsA total of 2891 subjects took part in the survey (1430 men and 1461 women).ResultsThe prevalence of obesity was 20·9 % in women and 6·0 % in men (P < 0·0001). The prevalence of overweight was 32·9 % in women v. 26·8 % in men (P < 0·0001). In women, the risk of obesity and overweight increased with age, with the highest risk being in individuals aged 45–54 years (OR = 3·02, 95 % CI 2·06, 4·44) compared to individuals <35 years old. Married women were more prone to obesity and overweight (OR = 2·42, 95 % CI 1·50, 3·91) than single women. In men, the risk of obesity and overweight increased with average family income (OR = 2·62, 95 % CI 1·40, 4·87 for family income ≥5000 MAD/month compared to <2000 MAD/month) and in married persons (OR = 3·75, 95 % CI 1·78, 7·81) compared to single individuals.ConclusionsThese results contribute to target groups in whom prevention programmes could be implemented.