Purpose: The purpose of this study was to examine the association between health behaviors and health-related quality of life (HRQOL) among vulnerable children in a community. Methods: Using data from ‘The Obesity Prevention Framework for Vulnerable Children``, a secondary analysis was conducted for 165 children (ages 8~12 years) and their parents who were recruited from 16 K-gu Community Child Centers in Seoul. Six types of health behaviors related to eating and activity were assessed. Each behavior was categorized into the non-recommended vs. recommended levels. The scores of the recommended levels of the six health behaviors were summed up for the composite score of health behaviors. HRQOL was measured by KIDSCREEN-52. Results: The groups with a non-recommended level of fast food intake and sedentary behavior had a significantly lower total score of KIDSCREEN-52 than those with a recommended level. Moreover, the lower composite score of health behaviors was significantly associated with the lower total score of KIDSCREEN-52. Conclusion: Among the vulnerable children, the six recommended health behaviors and their composite score were in significant positive associations with the HRQOL levels. Therefore, nursing strategies for enhancing the recommended levels of health behaviors are needed for vulnerable children.