The purpose of the present study is to investigate the pre-service science teachers' reflective thinking skills toward problem solving and the effects of gender, grade level, academic achievement, type of graduated high school and father and mother's education level on these skills. The study was conducted through the survey method with the participation of 126 pre-service teachers attending the department of Science Teacher Education of the Education Faculty at Mugla Sitki Kocman University in 2013-2014 academic year. Of the participants, 60 are first-year students and 66 are fourth-year students. In the study, as a data collection instrument, "Scale of Reflective Thinking Skills toward Problem Solving (SRTSPS)" developed by Kizilkaya and Askar was employed and the collected data were analyzed through SPSS 20.0 program package. In the analysis of the data, frequencies and percentages were calculated and t-test and one-way variance analysis (ANOVA) were used. At the end of the study, it was found that the pre-service teachers' reflective skills toward problem solving are low in general; they do not significantly vary depending on gender, grade level, academic achievement, type of graduated high school, mother's education level; however, significantly vary depending on father's education level.