In cholestasis, due to impossibility of gall flow into duodenum, there occurs a subsequent return of gall constituents to hepatocytes and circulation. Extrahepatic cholestasis is the result of mechanic obstacle of gall flow through ductus hepaticus, choledochus or papilla Vateri, leading to the occurrence of manifest icterus. In cases leading to liver damage, hydrophobic gall salts and non-conjugated bilirubins have the most important toxic effects.The aim of this study was to follow up the biochemical parameters, enzyme activity AST, ALT, *-GT and AF, bilirubin concentration and albumins, and intensity of oxidative stress in blood plasma in patients with different types of extrahepatic cholestasis.The study included 60 subjects divided into two groups. The first one was control group (30 healthy subjects), while II group involved 30 patients with intraluminar extrahepatic obstruction.Significant increase of enzyme activity of AST, ALT, *-GT and AF in plasma of cholestatic patients was present in comparison to the control group (p< 0,001). The levels of total direct and indirect bilirubin in plasma of cholestatic patients increased (p<0,001) when compared to the control group. The level of albumin in plasma of cholestatic patients significantly decreased in comparison to the control group (p<0,05). The intensity of oxidative stress measured through the levels of malondialdehide (MDA) and carbonyl group concentration in plasma of cholestatic patients increased (p<0,001) when compared to the control group.Significant increase of cholestasis enzyme markers (AST, ALT, *-GT and AF) and bilirubin levels in blood plasma was noticed in patients with extrahepatic cholestasis. Cholestasis leads to significant disorders of synthetic function of the liver that are manifested by decrease of albumin concentration in plasma