A 75-year-old man who was 162 cm tall and weighed 63 kg developed sudden back pain and dyspnea. He was diagnosed with a ruptured abdominal aortic aneurysm that was identified under the branch of the renal artery and underwent emergency Y-type artificial blood vessel replacement. He received 110 mg/day of dabigatran, and because his activated partial thromboplastin time was prolonged to 74.5 s, we administered idarucizumab to reverse the anticoagulant effects of dabigatran. Anesthesia was induced using ketamine, fentanyl, and rocuronium and was maintained with sevoflurane and remifentanil. After induction of anesthesia, we administered 5 g of idarucizumab to neutralize the anticoagulant action of dabigatran, and his activated clotting time significantly improved from 326 s to 109 s. Intraoperatively, we administered 100 units/kg of heparin for anticoagulation. After artificial blood vessel replacement, we administered 50 mg of protamine. After confirmation of hemostasis, surgery was successfully and safely completed without significant bleeding observed in the operative field. He reported no postoperative complications. Previous reports have described uncontrolled bleeding in patients receiving dabigatran, so we concluded that administration of idarucizumab was warranted in this case. This case report indicates that idarucizumab effectively reverses the anticoagulant action of dabigatran.