Aim. To assess the changes in hemocoagulation parameters according to the grade of renal dysfunction in elderly patients with cardiorenal syndrome types II and IV.Material and methods. In 56 patients of the elderly age group (mean age 78±10 y.o.), with coronary heart disease and chronic heart failure, the parameters of blood clotting were assessed and the relations with kidney dysfunction grade measured by the level of glomerular filtration rate (GFR). Patients were selected to 3 groups. In 47 (83,9%) there was decline of GFR <60 mL/min/1,73 m2, of those in 8 (17,3%) <30 mL/min/1,73 m2; in 9 GFR >60 mL/min/1,73 m2, with no signs of proteinuria (16,1%). All patients underwent coagulological assessment of the blood with measurement of the activated partial thromboplastin time, thrombin time and prothrombin time, international normalized ratio and fibrinogen concentration, as the complete blood count with platelet number, mean platelet volume, thrombocyte distribution width, and thrombocrit.Results. The number of platelets did differ significantly in groups 1 and 3 (p=0,040), as 2 and 3 (p=0,007). Thrombocrit values did differ significantly only in 2 and 3 (p=0,029). In the group 3 the rate of the mentioned values was below the respective reference values. Fibrinogen levels did differ significantly in groups 1 and 3 (p=0,042), and 2 and 3 (p=0,037). In the group 3 the parameter was higher than upper limit of reference range. Correlation found for GFR and fibrinogen level (r=-0,425; p=0,004), for GFR and platelet number (r=0,271; p=0,049). The platelet number correlated with creatinine level (ρ=-0,392; p=0,004). Creatinine level also correlated with fibrinogen level (ρ=0,375; p=0,012).Conclusion. In the elderly, with the decline of GFR there is decline of thrombocyte number and increase of fibrinogen concentration together with an increase of the severity of kidney dysfunction. The pathological changes that were found might probably serve as additional factor influencing the risk of adverse events related to disorder of blood clotting. The importance of the revealed relations, as the aimfulness for clinical application, should be evaluated in controlled studies.