The prognosis of patients with unresectable liver metastases is poor, even if hepatic arterial infusion chemotherapy (HAI) or systemic chemotherapy is administered. A pilot study was performed to evaluate the feasibility and efficacy of multimodality therapy with hepatectomy after HAI and portal embolization for such patients. Eight patients with colorectal carcinoma and synchronous unresectable liver metastases underwent resection of the primary tumor and placement of a pump, followed by HAI with 5-fluorouracil and mitomycin C. Owing to shrinkage of the liver metastases, two patients could undergo extended right hepatic lobectomy after portal embolization, which was deemed to be essential to prevent post-operative hepatic failure. The median survival time of the eight patients was 30 months, with a response rate of 75%. Complications including sclerosing cholangitis and duodenal ulcer were observed in five patients (63%). Additional hepatectomy could be performed successfully after portal embolization without morbidity in two patients. These two patients are still alive more than 6 years after initiation of HAI and have been free of disease for more than 5 years after hepatectomy. Hepatectomy after HAI and portal embolization is feasible and may be an option to cure selected patients with initially unresectable liver metastases.