The primary goal of this paper is to determine the trend of the nutritional status of early and preschool aged children and to see how important anthropometric measurement is in order to be able to react in the right way and on time. Also, the goal is to raise awareness of the current situation that is happening in the world, but also in Croatia regarding the nutritional status, where every third child is overweight. There are listed the health problems that arise due to malnutrition or overweight and how they can be prevented with a healthy lifestyle, which includes physical activity and healthy eating habits. Children who encounter these problems have various consequences and there are prevention measures to stop this from happening. There are a lot of different roles in the prevention of obesity, the role of: the family, the health system, kindergarten, the media and the food industry. Body weight, body height and BMI in percentile have been measured to assess the trend of nutritional status. The sample of participants were preschool children from five kindergarten groups in Zagreb, out of the 82 participants, both genders are represented (35 girls and 47 boys) aged from 4 to 6 years. Results have shown that most of the participants are in the group of normal body weight, but every fourth participant deviates from this criterion. According to the sample of participants, it turned out that there were more 4 year old's being overweight and obese than 6 year old's. At the end of this paper, it is concluded that anthropometric measurements of early and preschool age children should be performed at least once a year because they are of great importance in order to identify risks and to intervene in a timely manner.