Introduction: Catheter device closure of ventricular septal defect (VSD) has become an attractive alternative approach to surgery. Recently, device of Cocoon occlude was available in Korea, therefore we evaluated the early outcomes after VSD closure, retrospectively. Methods: We reviewed the medical records and angiographic images of total 11 patients who underwent transcatheter closure of VSD with Cocoon occlude in Samsung Medical Center. Results: Their median age was 4.9 years (3 months - 48 years). The procedure is performed under the guidance of transesophageal echocardiography except two patients. Devices were implanted at Muscular VSD (1), VSD on the fenestrated patch (2) and membranous VSD (8). The types of device were muscular type for 5 patients, membranous type for 3 patients, aneurysmal type for 2 patients and ductal occlude for one patient. The device was successfully implanted in all patients. But the echocardiography on the next day revealed small leakage in 5 patients (45.5%). In 2 cases, junctional arrhythmia and intermittent RBBB were observed after procedure. The arrhythmia was resolved after methylprednisolone pulse for 3 days. Two patients developed mild aortic regurgitation on the next day echocardiography and continued during follow-up. Complete closure rate was 54.5% at 3-month follow-up. Conclusion: Percutaneous closure of VSD with Cocoon occlude was technically possible but some complications were observed from our experience. Considering of learning period, we need more experiences and long-term data for the safe use of this device.