Objective: To identify and compare the sociodemographic determinants of stunting, wasting and overweight among infants of urban and rural areas in the Ecuadorian highlands. Design: Cross-sectional study. Setting: Nabon (rural) and Cuenca (urban) cantons, Azuay Province, Ecuador. Subjects: A total of 703 children aged 0-24 months and their caregivers (227 rural and 476 urban) recruited during the period from June to September 2008. Results: Stunting prevalence was significantly higher in the rural area (37?4 % v. 17?7 %; P , 0?001) while wasting (7?1 %) and overweight (17?1 %) prevalence were more similar between areas. Determinants of stunting for the pooled sample were male gender (OR Conclusions: Infant malnutrition was associated with different sociodemographic determinants between urban and rural areas in the Ecuadorian highlands, a finding which contributes to prioritize the determinants to be assessed in nutritional interventions.