Objective: We report our clinical experience with the Amplatzer device in transcatheter closure of 80 atrial septal defects (ASD) in children. Methods: Among 99 patients (mean age: 7.2±3.8 years) with ASD selected by transthoracic echocardiography, procedures were performed in 80 patients under general anesthesia with fluoroscopic and transesophageal echocardiographic (TEE) guidance. Optimal device size was selected after stretched balloon sizing of the ASD's. The patients were discharged at 24 hours after an evaluation with X-ray, electrocardiography and echocardiography. Results: The mean follow-up period (FUP) was 38±14 months. Mean ASD size was 11.5±3.7 mm at TEE (stretched size: 17.6±3.9 mm). The mean size of the device was 18.6±4.0 mm. Procedure and fluoroscopy time were 52.1±17.8 minutes and 11±4.9 minutes respectively. Immediately after the procedure 35 patients (43.8%) had residual shunts. Trivial shunt remained in only 2 of them (2.5%) after FUP. None of the patients had major complications. Minor and transient rhythm abnormalities were observed in 5 patients and trivial mitral regurgitation was seen in 6 patients. Conclusion: Amplatzer is an effective and safe device for transcatheter closure of ASD especially in pediatric patients.