Recently, the importance of sustainable development has been emphasized due to issues such as climate change, war, and global economic crisis, but the understanding of early childhood teachers, who are responsible for implementing sustainable development education, is not high, and the rate of sustainable development education in training courses is low. Therefore, the purpose of this study is to find future action plans by understanding the concept and level of awareness of pre-service early childhood teachers regarding Education for Sustainable Development (ESD). For this, we selected 29 third-year students currently enrolled in a three-year Early Childhood Education program at a university as participants. The concept map created by the prospective preschool teachers was analyzed in terms of upper concepts, hierarchy, feature scores, and density. The main results of this study are as follows. Firstly, the high-level concepts of ESD(Education for Sustainable Development) among prospective preschool teachers appeared similar in terms of sociocultural, environmental, and economic aspects. Secondly, both hierarchy and feature scores were higher for environmental aspects, whereas they were relatively low for sociocultural and economic aspects. Thirdly, the density results generally appeared to be similar. These results suggest the need to address the system of knowledge about ESD(Education for Sustainable Development) comprehensively in all subjects of the training process, to expand and deepen it