During percutaneous coronary intervention, coronary perforation is one of the most feared life-threatening complications, as it may cause cardiac tamponade or acute myocardial infarction. The incidence of this serious complication in recent years has increased from 0.2 to 0.6%, most likely due to the increase of complex procedures. However, the management of coronary perforation has not been established yet. We report the first case of coronary perforation successfully managed with intracoronary injection of hydrogel microspheres.