The purpose of this study was to investigate the effect of small group discussion activities using picture books on young children’s social competence. The research subjects were defined as follows depending on the purpose of this study: 1. How does small group discussion activities using picture books affect young children’s social competence? 1-1. How does small group discussion activities using picture books affect young children’s initiative of social competence? 1-2. How does small group discussion activities using picture books affect young children’s cooperation of social competence? 1-3. How does small group discussion activities using picture books affect young children’s sociability of social competence? The participants for this study were 48 children of 5 year age or 2 classes from K public Kindergarten located in K, Jeollabuk-do. The experimental group was selected 24 children(male 9, female 15) of 5 year age in A class, and the controlling group 24 children(male 11, female 13) of 5 year age in B class. The instrument for young children’s social competence was the Young Children’s Social Competence Instrument(Woo, 2002). Experimental group treatments had been conducted 16 times for 10 weeks from Oct. 8th(mon) to Dec. 14th(thu) in 2012 during the Free Choice Activities. Each 110minute observation were made from the first treatment through the sixth treatment and each 70minutes to the end of the treatment of this study. To test the research question, two group’s mean and standard deviations of social competence scores were calculated, and t-tests were conducted test group differences. The result of the study were as follows: The significant group differences of young children’s social competence was found(p<.001). First result means that small group discussion activities using picture books has positive effects on young children’s social competence. First, the significant group differences of young children’s initiative was found(p<.001). second result means that small group discussion activities using picture books has positive effects on young children’s initiative of social competence. Second, the significant group differences of young children’s cooperation was found(p<.001). third result means that small group discussion activities using picture books has positive effects on young children’s cooperation of social competence. Third, the significant group differences of young children’s sociability was found(p<.01). third result means that small group discussion activities using picture books has positive effects on young children’s sociability of social competence.