Objective：To investigate the short and medium-term effects of simultaneous maze Ⅳ on comorbid atrial fibrillation（AF）in patients underwent atrial septal defect（ASD）repair. Methods：The data of 28 patients with concomitant ASD and AF from February 2014 to May 2019 were analyzed retrospectively. All patients underwent ASD repair and maze Ⅳ procedure at the same time in our hospital. The surgical complications and the success rate of AF ablation from AF in medium-term follow-up was recorded. Results：The median follow-up was 2 years，with no deaths during the follow-up period. The success rates of AF ablation at 6 months，1 year，and 2 years after the operation were 85.7%，78.5%，and 78.5%，respectively. No pacemaker implantation needed due to atrioventricular block，and no stroke occurred during the follow-up period. Conclusion：ASD patients combined with AF should be treated with ASD repair and maze Ⅳ procedure at the same time，which does not increase the risks of surgery. The rates for maintenance of sinus rhythm in short-term and medium-term are satisfactory although the long-term results needs further research.