Radial artery perforation is one of the major complications of transradial percutaneous coronary intervention (PCI). Previous reports have suggested that sealing the perforation with a smaller guiding catheter may be possible. In one such study, the perforated segment was sealed with a 0.014- or 0.021-inch guidewire, and PCI was successfully completed. In this study, we describe a radial artery perforation that occurred after diagnostic coronary angiography and during insertion of a 6 French (FR) guiding catheter. PCI and the perforation were successfully managed through the use of a 5 Fr guiding catheter and a 0.035-inch guidewire.