Many environmental educators insist that environmental education (EE) should be started from a young age. The Korean Ministry of Education (1999) has also emphasized the importance of environmental education in early childhood by including content and objectives regarding EE in the 1999 National Curriculum of Kindergarten. However, many Korean kindergarten teachers do not sufficiently implement environmental education in their teaching practice. To address this issue, this study aimed at investigating and overcoming barriers to fully implement EE in the Korean kindergarten context. Four experienced Korean kindergarten teachers were involved in a fourteeniv week critical action research project that included weekly group meetings. At these group meetings, teachers reflected on the barriers preventing the full implementation of EE in their classrooms and discussed possible environmental education actions to be attempted in the following week. These actions, individually implemented in teachers’classrooms, were reviewed at subsequent group meetings. Data from group meetings and teacher lessons were used to analyze the effectiveness of this critical action research project for developing environmental education. At the beginning stages of this study, Korean kindergarten teachers felt strongly uncomfortable participating in group communication. However, through the continuous encouragement of the researcher and with the involvement of participants who have similar educational backgrounds, age, and working experiences, participants came to actively engage in group communication. Participants in this study identified the following barriers to fully implement EE in kindergartens: insufficient understandings and awareness of EE, reluctant attitudes towards the environment, lack of educational support and resources, low parental involvement, and discomfort about going on a field trip to environments. Teachers came to understand the importance, objectives, potential topics, and teaching methods of early childhood environmental education. While implementing environmental education in their classrooms, teachers recognized possibilities for environmental education through connections with children’s daily lives and previous activities conducted in their classrooms. Teachers also identified that critical action research through group communication provided practical and useful knowledge of their educational practices. Teachers’ improved pedagogical knowledge and awareness about EE increased their confidence to teach environmental education. To lessen the burden of going on a field trip to environments, teachers provided children direct experiences in the environment surrounding schools and during school picnics. Teachers also actively participated in environmental activities with children. These direct experiences of the environment helped teachers and children appreciate the beauty of the environment and change their reluctant attitudes towards the environment. By providing parents children’s products produced during EE, teachers were also able to help parents develop an interest in environmental education. While most educational research in Korean kindergartens is conducted by university-based researchers, this research inquiry revealed that action research by the effective partnership with a university-based researcher can encourage the confidence and passion of Korean kindergarten teachers to reflect and resolve issues arising from their experiences and to change educational practices.