The purpose of this study is to profile future science teachers' understandings of current environmental issues in the context of an education reform in Turkey. Knowledge base and understandings of elementary and secondary prospective science teachers about biodiversity, carbon cycle, global warming and ozone layer depletion were targeted in the study. Questionnaire surveys developed for this purpose were adapted and used in this investigation. The questionnaires were administered to 360 participants in six universities. Analysis involved frequencies, percentages and comparing means for students majoring in elementary and secondary science teaching. Analysis of variance for differences among majors and responses to different issues are also included. Findings are compared and contrasted with the previous research in other countries. The study has implications for the prospective preparation of teachers and the future of environmental literacy movement in Turkey.