In this study, we discuss pedagogical content knowledge (PCK) of pre-service environment teachers since PCK is one of the most important professional competencies for teachers. In Republic of Korea, environmental education is taught as an independent subject in middle and high schools. Thus, pedagogical content knowledge (PCK) of environment teachers plays an important role for quality EE at schools. The purpose of this study is to find out the PCK(Pedagogical Content Knowledge) of pre-service environment teachers. Researchers collected and analyzed data from four environmental education department. Study method used a questionnaire for eighty-two pre-service environment teachers. The study results are as follows. Seven part of PCK(Knowledge of Instructional Strategies, Knowledge of Representation, Knowledge of Subject Matter, Knowledge of Evaluation, Knowledge of Students, Knowledge of Curriculum, Knowledge of Environmental Context) exists the significant difference in pre-service environment teachers. The highest part is the Knowledge of Environmental Context and the lowest part is the Knowledge of Evaluation in pre-service teachers. So the curriculum of environmental education department will be changing that emphasize the Knowledge of Evaluation and the Knowledge of Students.