We aimed to assess hepatic histopathological responses to preoperative chemotherapy in patients with colorectal liver metastasis. We selected all patients(n=34)with colorectal liver metastases between September 2006 and March 2009. The preoperative chemotherapy group was significantly associated with tumor regression, inflammatory response, sinusoidal dilatation compared with non-chemotherapy group. There was no difference in the rate of postoperative complications and hospital stay. Prolonged preoperative systemic chemotherapy alters liver parenchyma, but it does not increase postoperative complications. This should be taken into consideration before deciding a major liver resection in patients who have received preoperative chemotherapy.