Objective: To compare the knowledge of mothers on food contamination in the home between the towns of Peru and Costa Rica. Methods: It was conducted in a rural area of Peru (San Pablo and Huascar) in San Juan de Lurigancho in Lima, and Costa Rica (San Vicente of Three Rivers). The questions were part of a scale that was validated on an expert opinion. It was developed to measure three components or domains.After validation,the instrument was applied in Costa Rica with a group of mothers or caregivers with children under five. The application was developed in Peru in a population with similar characteristics. Results:The sample consisted of 50 caregivers in Costa Rica and 194 in Peru. There is no significant difference in the domains of contamination utensils at home (p=O.750>0.05) and knowledge of child illness (p=0.060>0.05). Knowledge of agents of contamination was highly significant (...