Objective: This study aimed to reveal pre-service early childhood teachers’ perception of children’s environmental education using concept mapping and demonstrating its importance. Methods: Based on Kane and Trochim’s(2007) procedure, 33 pre-service early childhood teachers conducted brainstorming and statement writing, and then the importance of selected statements were rated by 202 pre-service early childhood teachers. Selected statements were analyzed through multidimensional scaling and hierarchical cluster analysis. Results: Pre-service early childhood teachers perceived children’s environmental education as concept mapping with 2-dimensions and eight clusters. The following eight clusters were established (1) daily practice through hands on experience, (2) nature environment, (3) recognizing and coping with environmental issues, (4) environmental preservation practices, (5) environmental sensitivity and consideration, (6) purpose of children’s environmental education, (7) necessity for children’s environmental education (8) Practice through connection with child’s home and community. And then among the eight clusters, the most important was recognized as ‘daily practice through hands on experience’, and among the statements ‘young children learn through the method of playing in nature and experience nature’ was considered the most important. Conclusion/Implications: Based on these results, we discuss the importance of children’s environmental education of pre-service early childhood teachers and how to support to develop teacher’s training program.