Asthma psychoeducational programs have been found to be effective in terms of symptom-related outcome. They are mostly illness-focused, and pay minimal attention to systemic/familial factors. This study evaluated a novel asthma psychoeducation program that adopted a parallel group design and incorporated family therapy. A randomized waitlist-controlled crossover clinical trial design was adopted. Children with stable asthma and their parents were recruited from a pediatric chest clinic. Outcome measures included, for the patients: exhaled nitric oxide (eNO), spirometry, and adjustment to asthma; and for the parents: perceived efficacy in asthma management, Hospital Anxiety and Depression Scale anxiety subscale, Body Mind Spirit Well-being Inventory emotion subscale, and Short Form 12 health-related quality of life scale. Forty-six patients participated in the study. Attrition rates were 13.0% and 26.0% for the active and control groups, respectively. Repeated-measures ANOVA revealed a significant decrease in airway inflammation, as indicated by eNO levels, and an increase in patient's adjustment to asthma and parents' perceived efficacy in asthma management. Serial trend analysis revealed that most psychosocial measures continued to progress steadily after intervention. Significant improvements in both symptom-related measures and mental health and relationship measures were observed. The findings supported the value of incorporating family therapy into asthma psychoeducation programs.