Objective This study assessed the relationship between urbanization and the double burden of malnutrition (DBM) in Peru.Methods A cross-sectional analysis of the Demographic and Health Survey (2009 to 2016) was conducted. A DBM "case" comprised a child with undernutrition and a mother with overweight/obesity. For urbanization, three indicators were used: an eight-category variable based on district-level population density (inhabitants/km(2)), a dichotomous urban/rural variable, and place of residence (countryside, towns, small cities, or capital/large cities).Results The prevalence of DBM was lower in urban than in rural areas (prevalence ratio [PR] 0.70; 95% CI: 0.65-0.75), and compared with the countryside, DBM was less prevalent in towns (PR 0.75; 95% CI: 0.69-0.82), small cities (PR 0.73; 95% CI: 0.67-0.79), and capital/large cities (PR 0.53; 95% CI: 0.46-0.61). Using population density, the adjusted prevalence of DBM was 9.7% (95% CI: 9.4%-10.1%) in low-density settings (1 to 500 inhabitants/km(2)), 5.9% (95% CI: 4.9%-6.8%) in mid-urbanized settings (1,001 to 2,500 inhabitants/km(2)), 5.8% (95% CI: 4.5%-7.1%) in more densely populated settings (7,501 to 10,000 inhabitants/km(2)), and 5.5% (95% CI: 4.1%-7.0%) in high-density settings (>15,000 inhabitants/km(2)).Conclusions The prevalence of DBM is higher in the least-urbanized settings such as rural and peri-urban areas, particularly those under 2,500 inhabitants/km(2)