An agarose gel electrophoretic technique which clearly detects and sharply resolves serum lipoproteins has been applied to the determination of serum lipoprotein patterns in liver diseases. The patterns obtained are characterized by presence of beta-, absence of pre-beta-, and trace of alpha-lipoproteins in portal cirrhosis; presence of beta-, pre-beta-, and alpha-lipoproteins in primary biliary cirrhosis; a densely stained beta- and absence of pre-beta- and alpha-lipoproteins in viral hepatitis during the first week of the acute phase and reappearance of pre-beta- and alpha-lipoproteins after 2 weeks in the recovering cases without complications. These data provide information on the variable nature and for differential diagnosis of these conditions.