It was established that in patients with local spread of carcinoma of the stomach the hemostasis system makes danger of thrombogenesis due to lowered reserved possibilities of fibrinolysis and aggregation activity of the vessel wall. The state of danger of thrombogenesis under such conditions realizes itself in thrombi of profound veins of lower extremities detected by the method of radioisotope phlebography at the preoperative stage of treatment in 32.5% of the patients. Radioindication with fibrinogen125 has shown that the progressing development of preoperative thromboses is observed in the postoperative period. Complex medicamentous treatment (heparin, rheopolyglucin, nicotinic acid, aspirin) in combination with the graded physical exercise of the lower extremity muscles in the postoperative period eliminates the danger of thrombogenesis and prevents the development of venous thrombotic complications.