In this retrospective study different characteristics of hospitalizations of adolescents were investigated, before and after the onset of COVID-19 pandemic. We analyzed the data related to inpatient admissions of adolescents (12-18 yr.) at the Department of Child and Adolescent Psychiatry, CHC Rijeka. Data were collected from medical documentation (software). Three one-year period were analyzed and compared: 2019, 2021 and 2022. The number of hospitalizations increased by 14% in 2022, along with a 11.5% decrease of first hospitalizations. Female patients were hospitalized in a higher proportion in all three years, with an additional increase in 2021 and 2022. There was a noticeable increase by 13.5% of hospitalizations of patients living in an institution. The hospitalizations of patients living with both of their parents decreased by 9%. In 2019 and 2021, most hospitalized patients were aged 16, while in 2022, most patients were aged 14 and 15. Conduct disorders were the most frequent diagnoses in all three years, with an increase in 2022. Suicidal ideation was the most frequent reason for hospitalization in 2022, showing an increase of 12.6%. These findings are in line with other studies that have shown an increase in numbers of inpatient admissions after the onset of COVID-19 pandemic. With the pandemic, children and adolescents had decreased social interactions, their routine was broken, which led to a great change in their lives. Most of research papers found analyzed the consequences of the pandemic in 2020 and 2021, but later consequences of the pandemic should still be examined.