The aim of the study. Assessment of dynamic changes in the expression of activators and inhibitors of coagulation and fibrinolysis in the neointima of polyester vascular grafts during their healing process.Material and methods. The study was carried out on 18 dogs that underwent replacement of infrarenal abdominal aorta with a polyester DALLON - double velour prosthesis. Grafts were removed after 1, 4 and 12 months and fixed according to the AMeX method. Immunohistochemical labeling for tissue factor (TF), tissue factor pathway inhibitor (TFPI), tissue plasminogen activator (t-PA), urokinase plasminogen activator (u-PA), plasminogen activator inhibitor type-1 (PAI-1), prothrombin activation fragment F1+2 (F1+2) and D-dimer (DD) was performed on the neointima of the grafts.Results. TF expression did not demonstrate any significant differences in all study periods. TFPI expression appeared at 4 months and was increased at 12 months. Intensive F1+2 expression was shown at 1 month; its mild expression was still present in the following periods of the study. Plasminogen activators were demonstrated at 1 month and their expression was increased at 4 and 12 months, whereas weak expression of PAI-1 and DD was shown in all study periods.Conclusions. High thrombotic potential of polyester vascular graft neointima is present in all periods of the graft healing process. Increasing TFPI and plasminogen activators expression in the late postoperative follow-up favors graft patency maintenance.