Background To study the clinical manifestations and advantages of open-heart surgery and echocardiographic transthoracic or percutaneous closure with secundum atrial septal defect (ASD). The surgeon's learning curve was also analyzed. Methods In all, 115 consecutive patients with ASD from May 2013 to May 2019 were enrolled. According to the operative procedure, patients were divided into three groups: group one (open repair group) (n = 24), where patients underwent ASD repair (ASDR) under cardiopulmonary bypass (CPB); group two (closed surgical device closure group) (n = 69), where patients (six patients <= 1 y and sixteen <= 10 kg) underwent transthoracic ASD occlusion under transesophageal echocardiographic (TEE) guidance; and group three (transcatheter occlusion group) (n = 22), where patients underwent percutaneous ASD occlusion under echocardiography. The clinical features and results of each group were analyzed. All patients were telephonically followed-up after 3 months. Results All the three methods treating ASD were successfully performed in our hospital. It was also a typical developing history of congenital heart disease (CHD) surgery in China. One patient in the group two was transferred to emergency surgery for occluder retrieval and CPB-ASDR. Eight patients experienced failed transthoracic or percutaneous occlusion, two of whom underwent unsuccessful percutaneous closure at another hospital. Two patients each in the groups two and three were intraoperatively converted to CPB-ASDR. Two patient in the group three was converted to transthoracic occlusion surgery. All patients were discharged without any residual shunt. The three-month follow-up also did not show any residual shunt and occluder displacement. Conclusion In low-weight, infants, or huge ASDs with suitable rim for device occlusion, transthoracic ASD closure was successfully performed. Based on knowledge of ASD anatomy and skilled transthoracic occlusion of ASD, surgeons can perform percutaneous occlusion of ASD under echocardiographic guidance.