There are problems of postoperative relapse of veins after radiofrequency ablation (RFA). The study aims to analyze the causes of postoperative recurrence of veins after RFA. 928 patients with varicose veins of the lower extremities, clinical classes C₂-C₄ according to the CEAP classification, were treated in the ambulatory surgery centers using RFA. The causes of varicose recurrence showed that it was caused by: a) high fusion of the anterior accessory great saphenous vein (AAGSV) with great saphenous vein (GSV) directly in the saphenofemoral junction (SFJ), which was not revealed by preoperative ultrasound (1.7%); a long stump of the GSV after the RFA (7.8%); progression of varicose disease with the small saphenous vein (SSV) and formation of new reflux associated with insufficiency of the saphenopopliteal junction (SPJ) (4.7%); d) insufficiency of perforating veins of the tibioperoneal group (Sherman, Boyd), as well as Gunter (3.8%); e) neovascularization with dilation of small vessels in the area of the saphenofemoral junction (0.97%). A comparative assessment of the quality of life (QL) after different surgery methods 3 years after implementation was carried out. Thus, QL in all patients who underwent surgery significantly improved than before surgery. However, after the RFA GSV+AAGSV, the patients had better QL by all scales than those who underwent only RFA GSV. Operations performed simultaneously on GSV and AAGSV have better functionality than GSV-only RFA.