Diagnostic importance of gamma-glutamyl transpeptidase and alkaline phosphatase activities estimation in bile was demonstrated during inflammation of biliary ducts and gallbladder. Activation of these enzymes in B-bile in cholecystitis and in B- and C-bile--in cholecystocholangitis enabled to perform topical diagnosis. Correlation between the enzymatic activity in bile and blood allowed to diagnose acute viral hepatitis B and its combination with inflammation of biliary cuts.