OBJECTIVES: Examine the frequency of thrombocytopenia, the outcome of treatment, whether there is age, sex, existing comorbidities, perinatal risk factors, family history influence the distinction in the occurrence of thrombocytopenia; examine the etiologic causes of thrombocytopenia, and the correlation of the clinical presentation, the number of platelets and the treatment of children with thrombocytopenia. STUDY DESIGN: A cross-sectional study with historical data. PARTICIPANTS AND METHODS: The research includes children with diagnosed thrombocytopenia who were hospitalized from 1 January 2017 to 31 December 2021 at the Paediatrics, University Hospital Centre Osijek. The data of the examinees were collected from the medical documentation: the general features of children, perinatal risk factors, laboratory parameters, and clinical features of the patient. RESULTS: Thrombocytopenia causes almost 1% of the hospitalization at the Paediatrics, University Hospital Centre Osijek. There is no significant difference in the hospitalization of male and female children. Median age at diagnosis is 4 in children who were on therapy and 10 in children under observation. Adiposity and existing comorbidities are more frequent in children who were on therapy. Just over half of hospitalized children had ITP as the cause of thrombocytopenia. Most of the children who were on therapy had ITP. Petechiae and fever are most commonly present in the clinical presentation. The most frequently used treatment was IVIG. CONCLUSION: Thrombocytopenia is one of the common causes of hospitalization. Thrombocytopenia equally affects male and female children. The most common cause of thrombocytopenia in children is ITP. Perinatal risk factors, family haematological history, and family history of autoimmune diseases do not affect the occurrence of thrombocytopenia. The occurrence of petechiae is larger in clinical presentation with lower platelet count.