The presence of high serum concentrations of immunoglobulins and hypocomplementemia is commonly observed in alcoholic patients; however, the mechanism behind their production is unknown. We studied 70 subjects (52 alcoholics and 18 healthy controls) prospectively. All the patients were active drinkers who consumed more than 100 gr of ethanol daily for at least 10 years. A biopsy of the liver was performed for all the subjects, along with immunoglobulins, C3, C4, CH100 and tests of liver function. Of the 52 alcoholics in the study, 20 showed minimal changes in hepatic steatosis (group II), 6 isolated severe alcoholic hepatitis (group III), 11 cirrhosis of the liver without alcoholic hepatitis (group IV), and 15 cirrhosis with alcoholic hepatitis (group V). There were no significant differences between the various groups according to age or quantity and duration of intake. The highest concentrations of immunoglobulins was observed in those with cirrhosis of the liver (p < 0.001) regardless of the degree of inflammation. The best correlation was found between IgA and liver histology (r = 0.64; p < 0.001). Hypocomplementemia was a factor only in those patients belonging to histological groups IV and V. Both the immunoglobulins and the complement proteins were narrowly correlated with the tests of liver function, and its alterations were more pronounced in patients with cirrhosis in Child's stage C. We conclude that the hypergammaglobulinemia and hypocomplementemia observed in the alcoholic patients are conditioned fundamentally by the degree of deterioration in liver function, indicated by cirrhosis of the liver upon presentation.