Numerous studies have concluded that physical activity contributes to both physical and mental health. The aim of the research was to examine the characteristics of the relationship between physical activity, self-esteem, and self-efficacy, as well as to describe the relationship between physical activity and locus of control. The study was conducted online with a sample of students from the Republic of Croatia. The research utilized the following questionnaires: Rosenberg's Self-Esteem Scale (Rosenberg, 1965), The General Self-Efficacy Scale (Schwarzer and Jerusalem, 1995), The Locus of Control Questionnaire (Rotter, 1966) and The Leisure Time Exercise Questionnaire (Godin-Shephard, 1985). A total of 153 participants took part in the study, with an average age of 22 years (M=22, SD=1.99)Young adults were selected as the target population because they are a group significantly affected by insufficient physical activity. However, they are generally still healthy and physically capable, meaning it is not too late to develop healthy habits. The results indicated a statistically significant difference in the level of physical activity between male and female students, with males being more active. Furthermore, the study found that physically active male and female students have significantly higher levels of self-efficacy compared to those who are insufficiently active. However, no significant differences were observed concerning self-esteem or locus of control. Following this finding, it was concluded that there is a low, but statistically significant positive correlation between physical activity and self-efficacy. No correlation was found between physical activity and self-esteem or between physical activity and locus of control. Regression analysis results indicated that predictors explained 9.4% of the variance in physical activity, with the level of self-efficacy emerging as the only significant predictor. Additionally, it is important to note that nearly half of the participants did not meet the recommended criteria for physical activity, with insufficient activity being particularly pronounced among female students. Young people should be educated and encouraged to engage in physical activity to prevent health issues that can be averted. To achieve the desired changes, adolescents should be offered a variety of activities, and attention should be drawn to parents and teachers regarding the positive effects of physical exercise, while also continuously working to combat gender stereotypes related to physical activity, especially concerning young women.