The purpose of this study was to examine the influence of taekwondo training on young children\'s self-esteem and social adaptability. The subjects in this study were 60 young children who were enrolled in classes of age 5 to 7 in kindergarten and daycare center in Seocho, Gangnam, Seoul. After an experimental group and a control group were organized with 30 children each, the experimental group underwent taekwondo training in optional classes five times a week. The training was conducted 70 times for 14 weeks, and each lesson lasted 50 minutes. The instrument used to assess the self-esteem of the preschoolers was Kim Yeoung-suk(1997)\'s revised version of Harter & Pike(1984)\'s Self- Esteem Scale for Five- and Six-Year-Olds, which was a preschooler self-awareness scale. To evaluate their kindergarten adaptability, the kindergarten adaptability segment of Lee Weon-yeoung, Park Chan-ok and Nho Yeoung-hee(1993)\'s Prosocial Inventory was employed, which adapted and modified McGrinnis and Goldstein(1990)\'s Skill Situations Measure. The collected data were analyzed with SPSS Ver. 13.0 program, and Independent-samples t-test and paired-samples t-test were utilized. The independent-samples t-test was implemented to see if the groups were equivalent and if they showed any improvement, and paired-samples t-test was carried out to look for any possible gaps between their pretest and posttest scores. The findings of the study about the research questions were as follows: First, taekwondo training served to foster the self-esteem of the preschoolers. Second, taekwondo training served to bolster the social adaptability of the preschoolers. Third, there was no difference between the preschool boys and girls in self-esteem and social adaptability. In conclusion, taekwondo training had a positive impact on the self- esteem and social adaptability of the kindergarteners who were at the ages of 5 to 7. ※ Key words : preschooler, taekwondo, self-esteem, social adaptability