This study was to investigate how cooperative art activities affect young children s social competence. Participants for this study were 40 five-year-old children attending two public kindergartens in Gwangju. The experimental group consisted of 20 children (ten boys and ten girls) of J public kindergarten, while the control group consisted of 20 children (ten boys and ten girls) of S public kindergarten. The instrument used in this study was Test for Social Competence (Lee, Lee, & Yang, 1988) which is the Korean version of Vineland Adative Behavior Scales (Sparrow, Balla, & Cicchetti, 1985). The experimental group had been treated with cooperative art activities, while the control group had been treated with general kindergarten curriculum based upon life themes. Cooperative art activities comprised sharing and talking on themes, making groups, doing art activities, and appreciating art works. Sixteen art activities had been administered to the experimental group from May 18 (Tuesday) to July 8 (Thursday), 2010. Results of this study were as follows. Cooperative art activities were found to positively affect young children s social competence. Cooperative art activities were found to positively affect young children s social activeness, social stability, cooperation, social participation and autonomy, compliance to social rules, leadership.