Twenty patients with unresectable hepatocellular carcinoma were treated by zinostatin stimalamer-transcatheter arterial embolization (SMANCS-TAE). After administration of SMANCS, a superselective catheterization technique was used to inject gelatin sponge particles into the artery or artery branch supplying the cancer-bearing segment. We compared the results of SMANCS-TAE with Lipiodol (Yamanouchi, Tokyo, Japan)-TAE performed during the same period. In 18 of 20 patients (90%), a tumor necrosis rate of 100% (grade 4) was obtained after one or two courses of SMANCS-TAE. The SMANCS group was superior to the Lipiodol-TAE group in terms of the tumor reduction rate, alpha-fetoprotein reduction rate, and cumulative 1.5-year survival rate, but not significantly. No severe side effects were noted after SMANCS-TAE. SMANCS-TAE appears to have potential as a new treatment for hepatocellularcarcinoma, and patients treated with this technique will be monitored to elucidate the long-term effects.