Hepatic arterial infusion (HAI) chemotherapy for unresectable liver metastases from colorectal cancer (CRC) is generally indicated to patients without extrahepatic lesions. This study was performed to examine whether or not it was possible to obtain a comparable survival time, response rate (RR) and modest toxicity combining low-dose LV and 5-FU (LV/5-FU) with HAI for the patients with unresectable liver metastases from CRC. Twenty two patients with unresectable multiple liver metastases were enrolled in the study. These were patients who had been admitted from 1994 to 2003 in our hospital. Patients were given LV at 25 mg/body immediately followed by 5-FU at 500 mg/body as a 2-hour HAI daily for 5 consecutive days every 5 weeks. The median survival time (MST) of HAI patients was 24.5 months. According to the treatment in the HAI patients, one patient was CR, 6 were PR, 9 were NC, 6 were PD, and the response rate (RR) was 31.8% (7 of 22 patients). The toxicities to this regimen on HAI were observed in 12 patients, and grades 3 or 4 were in 3 patients only. These results suggested that HAI with LV/5-FU can be useful for unresectable liver metastases from CRC.