Coronary artery perforation rarely occurs during or following percutaneous coronary intervention. Its consequences may range from minimal dye staining to tamponade and abrupt hemodynamic collapse. Coronary perforation during angioplasty can evolve into pseudoaneurysm. We report a case in which a vessel perforation and pseudoaneurysm were formed in the mid-portion of the left anterior descending artery during overlapped stenting. The perforation was sealed by inflating the angioplasty balloon. The patient was followed by angiography and intravascular ultrasound. After 1-week observation, the pseudoaneurysm was completely resolved.