OBJECTIVE: This survey explored prevalence of overweight and obesity and their associations with socio-demographic variables in a Nigerian population. METHODS: This cross-sectional survey involved 1521 adults in Nnewi. Age, sex, educational and occupational status, and BMI were recorded. RESULTS: Prevalence of overweight was higher in males (32.3%; 95% CI, 29.5%-35.2%) than in females (29.8%; 95% CI, 26.8%-33.0%); the reverse was the case for prevalence of obesity (19.6%; 95% CI, 17.3%-22.2% in males and 36.0%; 95% CI, 32.8%-39.4% in females). Higher odds ratios (ORs) for overweight and obesity were observed in participants aged 41-60 years (OR 2.03; 95% CI, 1.57-2.61 for overweight and OR 4.29; 95% CI, 3.25-5.67 for obesity) and those >60 years (OR 1.72; 95% CI, 1.21-2.43 for overweight and OR 4.21; 95% CI, 2.86-6.19 for obesity) compared to those aged 18-40 years. Female sex was associated with higher ORs for overweight (OR 1.20; 95% CI, 0.96-1.51) and obesity (OR 2.21; 95% CI, 1.73-2.83). Participants with secondary education had marginally higher ORs for overweight (OR 1.15; 95% CI, 0.88-1.51) and obesity (OR 1.17; 95% CI, 0.86-1.59) than those with tertiary education, and so were those with primary education for obesity (OR 1.19; 95% CI, 0.74-1.89) but higher OR for overweight (OR 1.44; 95% CI, 0.98-2.13). Unskilled participants had about the same OR for overweight and obesity as professionals, and while skilled participants had about the same OR for overweight as professionals, their OR for obesity (OR 1.27; 95% CI, 0.67-2.43) was fairly higher than that for professionals. CONCLUSIONS: Prevalence of overweight is higher in males than in females, but the reverse is the case for prevalence of obesity. Older age and female sex are associated with increased risk of overweight and obesity, while working at a skilled occupation is associated with obesity, and tertiary educational attainment is associated with overweight.