The purpose of this study was to identify factors influencing health-related quality of life (HRQoL) of overweight and obese children in Korea. This study employed a cross-sectional descriptive study design. A total of 132 overweight and obese children participated in the study. Anthropometric measurements included body mass index, percent body fat, and waist–hip ratio. The instruments included lifestyle patterns, psychosocial characteristics (stress, self-esteem, and depression), and HRQoL. The study found that significant predictors of HRQoL included self-esteem, depression, and physical stress; these variables accounted for 58.7% of the variance (p < .05), while children with low monthly household income had significantly lower HRQoL, compared with that of their counterparts (p < .05). HRQoL has multiple dimensions, thus, in addition to lifestyle change, health programs for overweight and obese children should focus on psychological health, and consider social and environmental factors as well.