Background. Mechanical jaundice (MF) and cholangitis are considered to be of great significance in emergency surgery due to their complex pathogenesis, risk of complications and high mortality. Objective. To establish the severity of hemostatic disorders in association with fibrinogen gene polymorphism (FGB (G(-455)A)) in patients with non-cancerous MF and cholangitis of varying severity. Material and methods. The subjects were 25 patients with benign MF and cholangitis divided into 2 groups: group 1 (n=12) – those with a mild form of the disease; group 2 (n=13) – those with a severe form. The research methods included the assessment of endogenous intoxication, liver function as well as blood coagulation activity. Genetic analysis of the FGB (G(-455) geneA)) was performed using a polymerase chain reaction by Real–time PCR. The severity of the disease was determined using the V.D. Fedorov scale (2000). Results. The early stage of MF and cholangitis is accompanied by endotoxicosis, resulting in the damage of a number of organs and systems, in particular the liver. The latter plays an important role in changing the activity of blood coagulation system. These disorders had a strong correlation with the severity of the disease: in mild cases, the character was less pronounced and reversible, and in severe cases – persistent and severe. Hemostatic disorders recorded in the early period of the disease depend on the severity: in mild cases, hypercoagulation and normofibrinolysis are noted, and in severe cases – hypocoagulation and hypofibrinolysis. Genetic polymorphism of the fibrinogen gene FGB (G(-455)A) had a significant impact on the pathogenetic process of MF and cholangitis. Patients with the mutant genotype (A/A) of the FGB gene were found to show the greatest severity of homeostasis system violation when compared with patients with genotypes G/G and G/A – with minimal imbalance. Conclusions. Hemostatic disorders associated with polymorphism of the fibrinogen gene FGB (G(-455)A) play an important role in the pathogenesis of MF and cholangitis.