Catheter ablation (CA) targeting premature ventricular contraction (PVC) from Purkinje fibers can be an effective therapy for refractory ventricular fibrillation (VF) after myocardial infarction (MI). We experienced two cases in which catheter ablation targeting PVC initiating VF after percutaneous coronary intervention (PCI) in post-MI patients was effective despite transient early recurrences of VF. The first patient (a 68-year-old woman with MI) developed drug-refractory VF 3 days after PCI to the left anterior descending artery (LAD) and left circumflex artery. CA targeting Purkinje potential preceding PVC at the infarcted area eliminated both the PVCs and VF. Three days after the procedure, the VF attacks relapsed by a different type of PVC. However, the VF responded to conventional treatments and disappeared thereafter. In the second patient (an 83-year-old woman with old MI), refractory VF attacks occurred after PCI to the LAD. CA targeting Purkinje potential preceding two distinct types of PVC successfully suppressed the VF. Although the VF relapsed 2 days after CA, it was suppressed by conventional treatment and disappeared the next day. .