This study suggests a novel approach, which integrates an explicit-reflective nature of science (NOS) instruction into the teachersas-researchers approach to improve pre-service science teachers' conceptions of NOS. Participants were 48 university fourth-year students in a four-year pre-service science teacher-training program in Turkey. The participants received explicit-reflective NOS instruction and were introduced to some techniques for critically evaluating academic articles, designing and conducting a research project, writing a research report and preparing materials to share the findings of their studies with students and staff of their department at a poster conference. During these activities, the lecturer explicitly addressed the target aspects of NOS and made pre-service science teachers' thinking more visible and reflective. The Views of Nature of Science Questionnaire (VNOS-C) was used in conjunction with individual interviews to assess participants' NOS views at the beginning and conclusion of the study. The results indicated that compared with their ideas at the beginning of the course, many pre-service science teachers had developed more ` informed ideas about NOS' throughout the course. The significance of this study is that carrying out an educational research with the incorporation of an explicit-reflective instructional model seems to be a promising avenue to improve pre-service science teachers' ideas about NOS. Some possible implications for pre-service and in-service teacher education and further research are discussed.