The introduction of monoclonal antibodies into the treatment protocols for metastatic colorectal cancer(mCRC)has significantly improved outcomes. There are some patients with mCRC, initially judged unresectable, who become resectable after chemotherapy. For patients with isolated liver metastases, surgical resection is recommended when feasible. We experienced a case in which an initially unresectable mCRC liver metastases converted into a resectable one after cetuximab monotherapy as third-line treatment. The sample from hepatectomy was a pathologically complete response; no remnants were detected. The management of liver metastases contributes to improvements in the clinical setting. For conducting a multimodal treatment of mCRC, the participation of various specialists such as medical oncologists, colorectal/hepaticsurgeons and diagnostic/therapeutic radiologists is indispensable. Furthermore, it is necessary to construct an evidence-based consensus on potentially resectable CRC liver metastases in each hospital.