Objective To evaluate the safety and efficacy of percutaneous closure for muscular ventricular septal defect(MVSD). Methods Fifty-one patients diagnosed as MVSD from October 2011 to July 2016 at Guangdong General Hospital were enrolled including 32 males and 19 females, ranging from 1 to 16 (5.12±3.52) years in age, weight (20.19±10.55) kg.The diameter of the MVSD was (4.82±2.51) mm which was measured by transthoracic echocardiography(TTE), and multiple defects were found in 10 patients.The choice of plugging device and transport system depended on the size, position and status of MVSD.TTE and left ventricular (LV) angiography were performed before and after release of the device to evaluate the therapeutic effects.Electrocardiogram and TTE were performed during follow-up period at 24 h, 1 month, 3 months, 6 months and 12 months after operation and yearly thereafter. Results Eight cases showed no hemodynamic significance through standard catheter examination then the interventional therapy was stopped.Cardiac arrest was found in 1 case when the long sheath was transported along the track, and the procedure was terminated immediately, and the selective surgical operation was performed after successful rescue.The devices were successfully placed in the rest of 42 patients (97.6%) with operation time (90.68±36.42) min and fluoroscopy time (18.67±10.89) min.The average of follow-up time was (13.82±13.84) months ranging from 1 to 48 months.It was found that mild residual shunts showed in 4 cases during operation, mild tricuspid regurgitation showed in 2 cases and trivial aortic regurgitation showed in 1 case at 6 months after operation, but there was no need to intervene anymore. Conclusions Percutaneous closure of MVSD in children is safe and effective with high successful rate and low incidence of complication.The middle-term follow-up findings were satisfactory. Key words: Congenital heart disease; Muscular ventricular septal defect; Transcatheter closure; Follow-up studies