Seventeen patients with hepatocellular carcinoma were treated by intraarterial injection of CTL suspension. The doses of CTL suspension, CDDP and THP(mean +/- SD)/injection were 4.1 +/- 1.6 ml, 81.9 +/- 31.6 mg and 13.5 +/- 5.2 mg, respectively. The therapy was given once in 10 patients, twice in 6 and 4 times in one. Over 50 per cent reduction in tumor size was obtained in 5 patients (30%). Fifty or more % decrease in serum alpha-feto-protein (AFP) levels was observed in 3 of 7 patients (43%) with the initial serum AFP level of more than 200 ng/ml, Fever, abdominal pain, nausea and vomiting were noted in most cases. However, they disappeared within 2 weeks after therapy was completed. No severe complications were encountered except one case of a liver abscess which healed by administration of antibiotics. No severe changes in laboratory data were observed. This study suggests that a new method of intraarterial injection must be developed to enhance the therapeutic effect even more, in addition to an increased injection dose of CDDP/THP-LPD and higher concentration of CDDP and THP in LPD.