The purpose of this study was to investigate the effect of cooperative group circle game on young children s social competence. For the purpose, following research questions were established; 1. How does cooperative group circle game affect young children s social competence? Subjects for the study were 40 five-year-old children attending a kindergarten attached to K elementary school in Geojae, Gyeongnam. The instrument for young children s social competence was the Young Children s Social Competence Instrument (Woo, 2002). To test the research questions, means and standard deviations of two groups pre- and post-tests were calculated, and then ANCOVA s were conducted to test group differences, putting pre-test scores as covariates. Results of this study were as follows: First, there was no significant group difference of young children s social competence. The activities of cooperative group circle game didn t affect young children s social competence in positive ways. Second, the significant group difference of young children s initiative was found (p < .05). The the activities of cooperative group circle game positively affected on young children s initiative. Third, the significant group difference of young children s cooperation was found (p < .05). The the activities of cooperative group circle game positively affected on young children s cooperation. Fourth, there was no significant group difference of young children s sociability. The activities of cooperative group circle game didn t affect young children s sociability in positive ways.