A report on 9 cases of infantile hepatopathy and cirrhosis of the liver respectively in cases of hereditary autosome-recessive alpha 1-antitrypsin deficiency (alpha 1-ATM). The genetic variants of the serum-protease-inhibitor (Pi) alpha 1-antitrypsin (alpha 1-AT) were examined by means of iso-electric focusing (Polyacrylamidgelen). The gene incidence was of the allel PiZ 0,0138 in the 868 blood donors from the Tyrol and was therefore within the range of the PiZ-frequencies seen in other Central-European populations. The other alleles PiM1, PiM2, PiM3, and PiS, point to the incidence of 0.7062, 0.1480, 0.1037, and 0.0225. The patients under observation (9) are homozygote PiZZ, the clinically healthy parents heterozygote PiZM. Risk of repetition in siblings of the patients is 25%. Early indicative symptoms are prolonged jaundice, acholic stools and hepatomegaly. Further developments are the fading of the hyperbilirubinaemia, temporary improvement in the pathological liver values, a freedom of symptoms for different lengths of time in each case, in the case of two patients, finally, decompensated cirrhosis of the liver and death in hepatic coma. The histological picture of the liver tissue shows PAS-positive storage granula in hepatozytes, intrahepatic hypoplasia of the bile duct, cholestasis as well as early cell necrobiosis, fibrosis and cirrhotic transformation. Course and severity of the liver complaint differ greatly, and are independent of the quantitative alpha 1-antitrypsin deficiency revealed, treatment is purely symptomatic.