Introduction and aim of the study: Creating and strengthening correct eating habits in preschool and school age is a basic element of developing healthy lifestyle in children. The greatest role in this significant period for developing specific eating behaviours is played by parents who are not only responsible for providing healthy food, but also the right example to follow. The aim of the study was to analyse children’s eating habits and physical activity depending on body mass index, level of education, and type of their parents’ activities. Materials and methods: The study was conducted in a randomly selected educational institution after obtaining the consent of the school’s headmaster. The participants of the study were children and their parents (N = 80; 52 girls and 28 boys) aged 6 to 13, residents of the Podkarpackie Voivodeship. Results: This study shows that mothers with a higher level of education are more likely than mothers with a lower level of education to have children with normal body weight or overweight (p = 0.026). More often, physical education classes were attended by children whose parents regularly take up physical activity, and the time spent by parents on physical activity during the week was a factor affecting their children’s participation in additional sports activities. The children of parents regularly taking up physical activity participated in them more often. Conclusions: Parents, through various processes and behaviours, instil in their children certain mechanisms which are important from the health perspective and can be helpful and contribute to the proper development of nutritional practices.