A possible pathogenetic role of selenium deficiency in alcoholic cirrhosis of the liver has previously been discussed. In the present study serum selenium was analyzed in 5 groups of liver diseases. The method used for selenium determination was electrothermal atomic absorption, after thermal stabilization of selenium compounds by addition of nickel nitrate. The selenium level of a reference group of healthy Norwegian adults (n = 40) was 1.53 +/- 0.25 mumol/l. The serum concentrations of selenium in patients suffering from alcoholic cirrhosis, chronic active hepatitis and chronic persistent hepatitis were lowered to 40-80 per cent of those of the reference group. In alcoholic cirrhosis and chronic active hepatitis the decreased serum selenium concentrations were significantly correlated to decreased levels of albumin and prealbumin.