Introduction: Mental illness is the most common cause of disability and a major public health issue worldwide due to its increasing prevalence, the difficulty of therapeutic treatment and the possible progression of the disease.

Objectives: To determine the prevalence of depressive symptoms in the student population over a 5-year period and the connection between sociodemographic characteristics and lifestyle habits of students and the occurrence of depressive symptoms.

Methods: A retrospective study was conducted in the period 2018-2022 at the Institute for Health Protection of Students in Belgrade. Data was obtained by analyzing the questionnaire completed by student including the PHQ-9 questionnaire. The difference between students' socio-demographic characteristics and lifestyle habits and the presence of depression was examined using the X2 test. Variables that were significant in the X2 test were included in a binary logistic regression. The data were analyzed with SPSS 20.

Results: 34047 students participated, 17.53% of whom were identified as individuals with high risk for depression. In the study first graders showed more symptoms of depression than third graders. The students who showed symptoms of depression were typically female, lived with their parents, did not consume alcohol or smoke and exercised 2-3 times per week. In the logistical regression model, alcohol consumption was positively and significantly associated with the presence of depressive symptoms.

Conclusion: The preventive measures should focus on lower alcohol consumption and frequent physical activity. Regular systematic examinations and referral to a specialist for the individuals identified as high-risk for depression should be mandatory.