For lay people, mass media are the main source of scientific information; that is why science journalists’ selection and depiction of scientific issues is an important field to study. This paper investigates science journalists’ general issue selection and additionally focuses on science journalists’ depiction of nanoscale science and technology and its related scientific evidence (certainty/uncertainty of research findings). Face-to-face interviews with science journalists (n = 21) from different German media channels were conducted. The results show that the professional role conception