Currently, transcatheter intervention is the preferred treatment for patients with anatomically suitable atrial septal defects. However, the use of nickel-titanium alloy occluders in interventional procedures results in lifelong presence of the implant in the body, leading to complications such as metal allergies and arrhythmias in some patients. To overcome the short-term and long-term complications associated with the presence of metal, and to avoid radiation exposure and metal toxicity, this paper reports a case of successful transcatheter closure of atrial septal defect in a pediatric patient with metal allergies using fully biodegradable occluder under ultrasound guidance, achieving excellent results by interventional therapy.