The aim of this Master's thesis is to study what public librarians' literature mediation looks like on Tiktok by exploring some librarians' experiences and perspectives and by mapping posts on the libraries Tiktok accounts to see which patterns emerge. The method for the study is qualitative semi-structured interviews with librarians as well as a quantitative content analysis of Tiktok-posts from the libraries where the interviewed librarians work. Analysis of the empirical material has been conducted within a thematic framework based on Jofrid Karner Smidt's mediation roles (1994). The key findings are that the librarian mostly acts as an educator and as a social anthropologist in the selection of literature, but that the librarian in the posts appears in the librarian's role as an ordinary person who conveys subjective experiences as a reader and tries to participate in the reading community Booktok on Tiktok. There is great possibility of designing videos on Tikok in order to reach users, but this requires knowledge of the aesthetics of the platform.