: Objective To analyze the clinical value of color Doppler ultrasound in detection of deep vein structure and hemodynamics of lower extremities of patients with great saphenous varicose vein. Method 90 patients (130 affected extremities) with great saphenous varicose vein were treated by Department of Vascular Surgery in our hospital from June 2015 to June 2016. Ultrasound was applied to observe the echo features of deep vein wall and valve of lower extremities, such as, lumen form, blood filling in the lumen, thrombosis situation. spectral Doppler imaging, and contrastive analysis was carried out with vein X-ray radiography. Results It was found from ultrasonic testing that among 130 affected extremities, there were 79 extremities with normal deep veins (accounting for 60.77%). There were 30 extremities with primary deep venous valve insufficiency (accounting for 23.08%), 4 extremities with deep venous thrombosis sequela (accounting for 3.08%) and 7 extremities complicated with arteriovenous fistula (accounting for 5.38%). Compared with X-ray venography, the accuracy of ultrasonic diagnosis was 96.2%, 93.3%, 100% and 100%, respectively. Conclusion Ultrasound can clearly display deep vein structure and hemodynamics of lower extremities of patients with great saphenous varicose vein, and it provides valuable help for diagnosis and treatment method selection.