This study attempts to suggest what role youth environmental organizations should play to grow into 'climate citizens' who consistently maintain awareness of climate change and act to bring about changes of social systems and policies even after they become adults. To this end, 'climate citizenship,' the closest concept to understanding people who actively solve the climate change problem, was adopted as an analysis framework. For the study, four adult subjects with experience in youth environmental organization activities were chosen. Then, by adopting a life history research method using narratives, it was analyzed how the experience of participating in youth environmental organization activities affected the formation of climate citizenship throughout their life. As a result of the study, participants could acquire 'meaningful experiences' such as forming relationships with peers and participating in decision-making through various hands-on activities. However, as an adult, no research participants had climate citizenship characteristics. Youth environmental organizations were successful in attracting youth attention and interest but did not play a significant role in laying the foundation for youth members to grow into climate citizens after they become adults. Therefore, this study synthesized the research results and suggested five improvements to ensure that the influence of youth environmental organization participation experience stays in the youth period and continues throughout adulthood. It proposes the improvement plans of more systematic and professional environmental education for the youth members, nationwide lifelong environmental education, operational improvement of environmental organizations to secure social trust, provision of various and balanced information and discussion-oriented education methods, and activation of national youth gathering.