Aim. This work is focused on the comparative analysis of the surgical and conservative strategies for the prevention of deep venous thrombosis and/or pulmonary embolism in the patients presenting with superficial thrombophlebitist of great saphenous vein, GSV (high ligation of (GSV) and anticoagulant therapy respectively). Material and methods. The present comparative prospective non-randomized study included 79 patients. The study group was comprised of 46 patients prescribed anticoagulant therapy with subcutaneous administration of unfractioned heparin (for 7-10 days) at an intermediate dose of 300 U/kg and the early onset (from day 1) of indirect anticoagulant (warfarin) at a starting dose of 5 mg. The treatment with warfarin lasted 3 months. Thirty three patients of the control group underwent high ligation of GSV whereas the prescription of heparin therapy was issued at the discretion of the attending physician. The frequency of deep venous thrombosis (DVT) in the lower extremities and/or of pulmonary embolism (PE) was assumed to be the criterion for the effectiveness of the treatment in both groups. Ultrasound scanning was performed at admission of each patient, on days 5-6 of hospitalization, upon discharge from the hospital, and 3 months after it. Lung perfusion scintiography was performed at admission and one month after discharge. Results and discussion. None of the patients of the study group developed either DVT or PE. In the control group, one (3.0%) patient developed femoral vein thrombosis and submassive pulmonary embolism after high ligation of DVT. Two patients in the study group experienced a rise in the level of thrombophlebitis that required crossectomy. One (2.2%) patient of the same group suffered overdosing of vitamin K antagonist (warfarin) resulting in weak nasal bleeding. Two (4.3%) patients experienced ST progression up to the saphenofemoral junction which required the high ligation. Twelve (36.4%) patients in the control group exhibited complications of crossectomy, hematoma, lymphorrhea, and lymphocele. Conclusion. Anticoagulant therapy of general duration 3 months with the use of intermediate doses of unfractioned heparin at the initial state of the treatment followed by warfarin intake is an effective method for the prevention of the development of DVT or PE in the patients with acute ascending varicothrombophlebitis of great saphenous vein.