ABSTRACTPreschool is an important period for the development of healthy lifestyle behaviors. Parents have a great influence upon a child developing healthy lifestyle behaviors. The purpose of this study was to determine the self-efficacy perceptions of parents related to their preschool children’s healthy eating and physical activity behaviors. This study was conducted with a research population of 425 parents of 3- to 6-year-old children. The data collection tools included Demographic Information Form, and The Parental Self-efficacy Questionnaire (PSQ). Also, the weight and height of the children and their parents were measured. There was a positive correlation in parental self-efficacy score between parents’ educational status and economic status and there was a significant negative correlation between children’s body mass index and parental self-efficacy scores. The understanding of the effect of parental self-efficacy perception in the development of preschool children’s healthy eating and physical activity behaviors is one of the first important steps in effective health promotion interventions.