Objectives: Childhood obesity is increasing in Latin America as nutrition status and economies transition. Peru is one such country with an emerging childhood obesity epidemic. The Peruvian Ministry of Health established goals for achieving reductions in overweight and obesity prevalence among children 5 years and younger by 2021. However, specific intervention strategies for achieving these goals are lacking. Culturally appropriate interventions guided by evidence-based theories are needed to address the emerging problem of overweight and obesity among young children. This study utilized the Pen-3 model, a culture-based conceptual framework to explore barriers and facilitators to healthy diet and physical activity for parents of young children in pueblos jóvenes communities. Design: A qualitative investigation was conducted as part of a larger cross-sectional survey study of parents of three and four-year-old children at five school sites in the peri-urban slum neighborhoods of southern Lima. Parents were asked to describe barriers and facilitators of healthy diet and physical activity for their preschoolers and families. Thematic analysis guided by PEN-3 model constructs assisted in identifying emergent themes. Results: Two domains of the Pen-3 model guided the elucidation of barriers and facilitators of health behaviors deemed essential to healthy diet and physical activity. Parental perceptions about neighborhood safety, lack of community resources, such as parks and recreation spaces, and lack of information about appropriate serving sizes and healthy recipes were identified as barriers. Facilitators to healthy behaviors included mothers’ views on their role as nurturers, and personal values for family-centered health behaviors. Conclusions: Parents identified specific barriers and facilitators of eating healthy and physical activity for their preschoolers and families living in resource poor areas of Peru. Health promotion professionals can utilize findings to inform the design of culturally appropriate family-based interventions in Peru’s pueblos jóvenes.