This study examined the relationships between asthma knowledge, behavior management, and social adaptation among school-age children with asthma. A total of 210 school-age asthmatic children and their parents were recruited from a medical hospital in Taiwan. The children completed asthma knowledge and behavior management questionnaires, and their parents completed the Child and Adolescent Adjustment Profile. There was a statistically significant positive correlation between behavior management and social adaptation among asthmatic children. Asthma knowledge and behavior management were positively associated but did not correlate with children's social adaptation. The behavior management of the children acted as a predictor of their social adaptation. These findings suggest that efforts to raise children's asthma knowledge will benefit these individuals in terms of behavior management. The introduction of asthma behavior management plans could facilitate the social adaptation of asthmatic children and, in particular, increase their independence and reduce their withdrawal as well as enhance their self-confidence and self-esteem.