Objective To analyze the effect of endovenous laser ablation combined with foam sclerotherapy on vascular endothelial function and coagulation function of patients with varicose veins of lower extremity. Methods A total of 120 patients with varicose veins of lower extremity treated in The Second People's Hospital of Nantong from July 2018 to June 2019 were selected and divided into two groups by the random number table method. Patients in the control group (60 cases) were treated by high ligation of great saphenous vein combined with segmental stripping, while patients in the observation group (60 cases) were treated with endovenous laser ablation combined with foam sclerotherapy, all patients in the both groups were followed up for 3 months after operation. The clinical efficacy 3 months after operation, the pain before operation and 14 days, 3 months after operation, vascular endothelial function and coagulation function indexes before operation and 3 months after operation, and the occurrence of post-operative related complications of patients in the two groups were compared. Results The total clinical effective rate in the observation group was higher than the control group 3 months after operation, but the difference was not statistically significant (P>0.05); compared with before operation, the circulating endothelial cell (CEC), serum endothelin-1 (ET-1) and plasma fibrinogen (FIB) levels of patients in the two groups significantly decreased 7 d after operation, and the observation group was significantly lower than the control group; while the nitric oxide (NO) level significantly increased, and the observation group was significantly higher than the control group (all P<0.05); however, there was no significant difference in the prothrombin time (PT) and activated partial thrombin time (APTT) before operation and 7 d after operation intra group and inter group comparisons (all P>0.05); compared with before operation, the visual analog pain scale (VAS) scores of patients in the two groups showed a trend of significantly decreased from 14 d to 3 months after operation, and the observation group was significantly lower than the control group; the total incidence of post-operative complications in the observationgroup was significantly lower than the control group (all P<0.05). Conclusion Endovenous laser ablation combined with foam sclerotherapy in the treatment of varicose veins of lower extremity can achieve good clinical effect, compared with high ligation of great saphenous vein combined with segmental stripping, which can reduce pain, improve vascular endothelial function, stabilize coagulation function, and have fewer post-operative complications.