Hepatic arterial infusion chemotherapy using totally implantable reservoir was performed for the treatment of liver metastases of colo-rectal cancers, and the therapeutic effects, side effects and complications were evaluated. Reservoir catheters were implanted into hepatic artery via gastroduodenal artery during operation. Mitomycin C (MMC), adriamycin (ADM), and 5-fluorouracil (5-FU) were used as chemotherapeutic agents. Eleven cases of H1 (metastases in one lobe only), 7 cases of H2 (a few scattered metastases in both lobes) and 12 cases of H3 (multiple metastases in both lobes) were treated intermittently with one-shot administration of MMC or ADM (A-group). Ten cases (H1: 1, H2: 2, H3: 7) were treated with intermittent one-shot administration of MMC or ADM following two-week continuous infusion of 5-FU through infusion pump after operation (B-group). In 5 of 10 cases of B-group, serum CEA level fell below the preoperative level, and the tumor size regressed in 3 of those 5 cases which were evaluated on the basis of CT scan. But no remarkable change in CEA level or tumor size on CT scan was seen in A-group. No particular side effect such as leucopenia, liver dysfunction or gastroduodenal symptom was noted except one case developing multiple gastric ulcers and pancreatitis in B-group. Five cases (25%) showed obstruction of catheter and 3 cases (14%) evidence leakage of chemotherapeutic agents in A-group. Three cases (30%) in agents in A-group. Three cases (30%) in B-group displayed obstruction of gastroduodenal artery beyond the tip of catheter. Median survival time of both groups (A, B) was 6 months and 12 months, respectively. The treatment seemed effective for the improvement of serum CEA level and tumor size, and there was a tendency toward prolongation of survival time in B-group.