The purpose of this study was to investigate the understandings of graduate students in biology education department about the aspects of nature of science. The study was conducted with case study methodology and included four graduate students. Questionnaire of definitions and VNOS-C (Views on Nature of Science Questionnaire-C) as data collection tools were used. The results indicated that "biology education" graduate students showed misunderstandings about "tentativeness", "objectivity", "social and cultural embeddedness of scientific knowledge", "hierarchical relationship among hypothesis, theory and law", "definition of science" and" creativeness and imagination in science". In addition, the participants presented discipline-dependent understandings. In this paper, the results of the study are discussed and limitations and important points of the study are explained for further research.