α-1-Antitrypsin deficiency due to homozygous Pi ZZ state is reported to be associated with cirrhosis and hepatocellular carcinoma (HCC); however, the role of heterozygous Pi Z state is not definitively known. In order to investigate the possible association, we studied the phenotypic distribution of α-1-antitrypsin variants (Pi) in 124 cases of HCC. Two thousand ten normal American Red Cross blood donors were studied as controls. Twelve patients with HCC had aberrant pheno-types, an incidence of 9.67% as compared to 8.36% among normal controls. Nine of 12 patients with HCC with aberrant Pi type had cirrhosis; 5 of the 9 had cirrhosis due to hepatitis B virus; 2 of the 9 had alcoholic liver disease with cirrhosis, and 2 had cryptogenic cirrhosis. The three patients with HCC arising in noncirrhotic livers who also had aberrant Pi phenotypes, had a relatively rare variety of HCC called fibrolamellar type. Z gene was found in five patients: all five were MZ. Incidence of MZ phenotype in HCC was similar to that of the normal control population (4.0% in HCC and 2.9% in the controls). However, 3 of 5 MZ were associated with fibrolamellar HCC. Another aberrant phenotype found among the patients with HCC was MF (fast moving) which occurred with an incidence of 2.41% as compared to none in the control group. In conclusion, we found no significant increase in the incidence of Z gene among 124 patients with HCC as compared to the normal population.