Objective To investigate the algorithm and efficacy of interventional treatment for combined congenital heart diseases. Methods Thirty-four patients (12 males and 22 females) with combined congenital heart disease underwent simultaneous transcatheter therapy. The types of the congenital heart defect combination were as follow: ASD and PS (16 cases); ASD and VSD (7 cases); ASD and PDA (3 cases); ASD and MS (2 cases); VSD and PDA (3 cases); Taussig-Bing and PDA(1 case); PDA, ASD and PS (1 case); ASD, VSD and PDA (1 case). The algorithm of transcatheter intervention was: PBPV or PBMV at first followed by the occlusion of VSD, PDA and ASD successively. Transthoracic echocardiography (TTE) and X-ray examination were done 3d, 1 m and 3 m after the procedure to evaluate the outcome of the procedure. Results All patients were treated successfully at one time. No complications occurred during and immediately after the procedure. There was no residual shunt and all the occlusion devices were found in the suitable site evaluated by means of TTE and X-ray right after the procedure. In 16 patients with ASD and PS, the systolic pressure across the pulmonary valve decreased from (53?20) mm?Hg to (14?10) mm?Hg (P