The purpose of the current study is to investigate pre-service science teachers' sustainable environmental education attitudes and the factors affecting them in terms of some variables (gender and grade level). The study group of the current research is comprised of 154 pre-service teachers attending the Department of Science Education in the Faculty of Education of Aksaray University. The study employed the descriptive survey method, one of the qualitative research methods. As the data collection tool, "The Sustainable Environmental Education Attitude Scale" developed by Afacan and Demirci Güler (2011) was used in the study. The Cronbach alpha reliability of the scale was calculated to be a = 0.93. In the statistical analysis of the data, SPSS was used. In the analysis of the data, Independent Samples t-Test and One Way ANOVA were run. The analysis results revealed that sustainable environmental education attitudes frequency of the pre-service teachers is at the medium level. It was also found that the sustainable environmental education attitudes of the pre-service teachers do not vary significantly by gender; yet, they were found to be varying significantly depending on the grade level variable. It can be suggested that further research can attempt to determine the attitudes of pre-service teachers from different branches and to analyze different factors affecting sustainable environmental education attitude.