The aim of this thesis was to determine whether there was a connection between the level of nutrition and physical activity in students from 1st to 4th grade. There were 165 respondents who participated in the research; 50.3% were girls and 49.7% were boys. To determine the level of nutrition, anthropometric measurements were performed, and the body mass index was calculated. The subjects were classified into the appropriate level of nutrition according to the results of the survey. The Croatian version of the PAQ-C questionnaire was used to determine the level of physical activity. Furthermore, the association between the level of nutrition and physical activity was calculated using the Pearson correlation coefficient. A t-test for independent samples was used to determine differences in relation to gender and age. When observing the nutrition of the respondents, no statistically significant difference was identified regarding gender. However, statistically significant difference was observed regarding age, with the value of the indicator being the highest for the 4th grade respondents. On the contrary, in the case of physical activity, there was a statistically significant difference regarding the gender of the respondents, whereby the value of the indicator was higher for male respondents, but there was no statistically significant difference regarding the age of the respondents. The test statistic that determined the relationship between the level of nutrition and physical activity shows that there is a statistically significant relationship between the level of nutrition and physical activity.