This study aims to explore the influence of nature of science (NOS) activities based on explicit-reflective and historical approach on preservice elementary teachers' views of NOS aspects. Mixed-method approach including both qualitative and quantitative methods was used. The sample consisted of 83 preservice elementary teachers of a public university. Activities in experimental group were prepared as per explicit-reflective approach, whereas per historical approach in the other group. Views of NOS questionnaire was applied both as a pretest and posttest to explore students' views about NOS aspects. During a 3-week application, worksheets were used and we benefited from observation checklists to control potential threats to internal validity. While content analysis method was used in qualitative analysis; frequency, percentage, Wilcoxon sign and Mann-Whitney tests were facilitated in quantitative part. Results indicated that students who experienced explicit-reflective instruction made statistically significant gains in their views of NOS aspects and accordingly some implications were presented.