Arterial infusion therapy with implantable reservoir was performed for forty-seven cases with unresectable hepatocellular carcinoma since 1986-1991. The one-year survival rate of cases of arterial infusion therapy with implantable reservoir was 50.6% and the 2-year survival rate was 37.8%. The survival rate was 51.4% and 32.2%, respectively, in the TAE cases for the same period. Considering the kinds of reservoirs used for HCC, the survival curve of 23 cases with double lumen reservoir showed a significantly better pattern than that of 24 cases with the usual single lumen reservoir (p less than 0.05). Cumulative usable rate of reservoir was 78.6% at one year, and 42.4% at two years (Kaplan-Meier method). Therapy after the reservoir was unusable, particularly with arterial obstruction by catheter, was restricted because arterial infusion therapy was impossible. It is considered very important to retain the hepatic artery because arterial infusion therapy is mainly for unresectable hepatocellular carcinoma.