Atrial septal defect (ASD) is a defect between right and left atrium. Nowadays, percutaneous closure using an atrial septal occluder (ASO) device is the preferred treatment for secundum ASDs due to its minimal invasiveness and high success rates. Although rare, device dislodgement can occur and may require surgical retrieval. This retrospective case series from RSUP Dr. Sardjito Hospital (January 2022- July 2024) reports three paediatric cases of failed ASD closure due to ASO dislodgement. The patients were aged 9, 12, and 13 years. Dislodgement occurred three years postimplantation in one patient, two months post-implantation in another, and intraoperatively in the third. Migration sites included the left atrium and right ventricle. Surgical removal and patch closure were performed in all cases. Cross-clamp times ranged from 20-24 minutes and cardiopulmonary bypass times from 34-46 minutes. All patients successfully recovered and were discharged without residual defects or further complications. Possible causes of ASO dislodgement include undersized devices, large defects, poor rim support, and procedural factors. Despite the children's relatively normal body weights, improper anchoring or anatomical limitations may have contributed to the device failure. While percutaneous retrieval is possible, chronic dislodgements are best managed surgically. No major complications, such as rupture or embolism, occurred postoperatively. In conclusion, although ASO dislodgement is rare, timely surgical intervention is essential. Since asymptomatic cases may remain undiagnosed, regular follow-up is crucial to detect delayed dislodgement.