This study investigates the reading preferences of young users of public libraries located in different districts of Tehran. The study uses a quantitative bibliometric method. It was carried out through an analysis of the online borrowing data recorded in the circulation departments of six Tehran public libraries ranked 3 by the Iran Public Libraries Foundation. The books borrowed by 12–18-year-old library users were analysed using Excel. The data shows that the users, regardless of their gender, preferred to borrow books not related to their coursework (non-supplementary books). Novels, adventure stories and fantasy were the genres most preferred by the users. Male and female youth, however, exhibited different reading preferences.