This thesis generally speaks about the concept of obesity, as well as the causes of its emergence and the consequences that it can elicit. The purpose and goal of this thesis is to determine if obesity occurs even in preschool age, and if so, to awake the society about that problem and many problems it can cause in a child. To prevent obesity in childhood age it is important that parents and educators are informed with the problem, as well as being aware of the risks they put children through in case of improper diet and encouragement of irregular way of life, which amongst all, causes lack of physical activity. All in all, it is important to arise children in their own example because they learn best from the life of their loved ones. Unfortunately, children today tend to learn through media that is all around them. Because of that, the parents and educators role is essential, so they can provide true values and plant healthy life habits. This thesis includes the description of the research conducted on 1st March, 2019 . The participants of the research were preshool children from kindergarten „Šareni svijet“ in Požega including 22 children of both gender (7 boys and 15 girls). For determination of the obesity and other states of nourishment, abdominal and hip circumference were measured, as well as body height and weight, which helped to calculate body mass index subsequently. The results have shown that the obesity shows even in this small amount of examinees.