The purpose of this study was (1) to examine general aspects of Korean school-age children’s self-reported quality of life(QOL), (2) to investigate what factors were related to the QOL of school-age children. Participants were 972 Korean 4th, 5th, & 6th grade students. Children completed a questionnaire based on the KIDSCREEN(The KIDSCREEN Group Europe, 2006) to evaluate their self-perceived well-being and subjective health. Major findings were as follows: 1. Upper grade students showed lower levels of QOL and boys reported higher levels of QOL than girls. Especially 6th grade girls showed the lowest QOL. 2. There were statistically significant relationships among 10 sub-dimensions of QOL (10 sub-dimensions: physical well-being, psychological well-being, moods & emotions, self-perception, autonomy, parent relations & home life, social support & peers, school environment, social acceptance, and financial resources). Specifically, ‘psychological well-being’ and ‘moods and emotions’ were strongly related with all the other sub-dimensions. This result suggested that experiencing more positive emotions(joy, pleasure, cheer), and less negative emotions (depression, anxiety, loneliness) tend to positively related to children’s QOL. 3. Physical health status didn’t have significant impact on school-age children’s QOL. It means whether children have diseases or not, the way how they recognize their well-being and subjective health has greater impact on children’s QOL. 4. Peer relationship and scholastic performance were found to be the significant factor that contribute to the QOL to both boys and girls.