Background: We performed a prospective observational study to compare the results of surgery and anticoagulation in patients with superficial vein thrombosis (SVT). Patients and methods: A total of 190 patients (195 limbs) with varicose veins and SVT were included and treated by anticoagulation or by surgery. Patients were followed-up during 6 months. The primary outcome for treatment efficacy was the composite rate of SVT extension/recurrence; deep vein thrombosis (DVT) or symptomatic pulmonary embolism (PE). The primary outcome for safety was the rate of wound complications and rate of bleedings. Results: Surgery was performed in 85 (44.7%) patients and 105 patients (5 with bilateral SVT) were treated conservatively. In the whole study cohort the primary outcome for treatment efficacy was registered in 15 (7.6%) cases: 9/85 (10.5%) in surgical group and 6/110 (5.4%) in anticoagulation group. Nine patients treated with surgery were diagnosed with postoperative DVT. In anticoagulation group SVT extension occurred in 3 limbs; SVT recurrence in 2 and DVT in one. There were no cases of PE or death during the follow-up. Time-to-event analysis demonstrated no significant difference between groups (HR 0.48; 95% CI 0.17-1.34). The total length of the thrombus was associated with primary efficacy outcome in surgical group (HR 1.07; 95% CI 1.02-1.11); and duration of anticoagulation (HR 0.91 per day; 95% CI 0.83-0.99) and value of Caprini score (HR 1.86; 95% CI 1.1-3.14) in anticoagulation group. Six (7%) wound complications were registered after surgery and 6 (5.71%) bleedings during anticoagulation. Conclusions: Urgent surgery is not associated with reduction of venous thromboembolism compared to anticoagulation in treatment of patients with SVT and varicose veins during 6-months follow-up. However, in patients with isolated thrombosis of varicose tributaries or with limited involvement of the saphenous trunk surgery is relatively safe.