Objectives: The aim of this study was to analyse drug therapy problems of hospitalized patients identified during the pre-registration training of the fifth-year students of the Faculty of Pharmacy and Biochemistry, University of Zagreb. Subjects and methods: Students collected patient data in the period from 2016. to 2018. Data included basic patient information, comorbidities, adherence, medication history prior to hospitalization, prescribed medicines during the hospitalization and laboratory tests. Drug therapy problems were evaluated according to Cipolle et al. classification (2012). Results: There were 72 students included in the study who collected data from 75 patient. The median of patients' age was 65,5 years (range 41 – 88), and patients presented with median of 6 comorbidities (range 2 – 14), and 10 medications (range 3 – 20). Every patient had at least one drug related problem, while on average 5,8  2,9 drug related problems per patient were identified. The largest proportion of patients (n=15; 20 %) had 4 drug related problems. Students detected 47,2 % of the drug related problems. The most common causes of drug related problems were adverse drug reactions (n=110, 25,2 %, students n=46, 22,3 %) and dose being too high (n=81, 18,6 %; students n=43, 20,9 %). Conclusion: Although students identified large number of drug therapy problems, we perceived the need for the improvement. This work emphasizes the importance of developing skills for drug therapy problems identification during the undergraduate studies. We believe that empowering students with such skills could ensure the development of professionals competent for pharmaceutical care provision and could greatly contribute to the positive outcomes of the treatment.