Atrial septal defect (ASD) is a common congenital heart disease with left-to-right shunt that may lead to pulmonary hypertension over time. Secundum ASD closure with transcatheter technique is currently the preferred method. The aim of this study was to evaluate the clinical experience and early-term outcomes of patients treated with a MemoPart ASD occluder device between June 2013 and June 2019. Fifty-six patients (35 females) with a mean age of 9.4 +/- 6.6 years (range: 2-44 years) were included in the study. The diameters of the devices used to close the ASDs were 7-28 mm. The ratio of the device/defect diameter was 1.14:1. Atrial septal defect closure was applied successfully in all patients. The MemoPart septal occluder is a safe and effective device for ASD closure. In wide ASDs and cases with more than one deficient rim, weak rims, or wide and complicated cases, it can be used carefully with sufficient experience.