Physical activity is extremely important for the health of the human body. It greatly contributes to mental and physical health. In preschool age, physical activity affects the growth and development of children, the development of motor skills, and for this reason it should be included in the regular activities of every child. Physical activity affects the development and strengthening of muscles, bones and internal organs, and in addition to positive effects on physical development, it also has a positive effect on the child's psychological development. A child who regularly engages in physical activity is less likely to develop obesity and is less prone to diseases. Physical activity, in addition to preventing certain diseases, can also mitigate or even eliminate the risk of disease occurrence.For this reason, it is of great importance that children engage in physical activity. In a preschool institution, it is the educators and the institution itself that must provide the children with all the necessary conditions for maintaining it. Educators should offer children a variety of interesting, high-quality content that will enable children to meet (satisfy) their needs. Activities can be part of physical education, morning exercise, sports training, walking or other entertainment. Outside the institution for early and preschool education, parents have an important influence on children. They are the people who influence their children the most. Children watch the habits of their parents, and for this reason, it is most important that parents teach their children healthy habits from an early age, to engage in regular physical activity and to include their children in them.The aim of this work was to point out the importance of physical activity, how it affects the child's organism and what is its role in the child's health.