Objective:To study the clinical value of color Doppler ultrasonography in the diagnosis of persistent sciatic vein(PSV).Methods:A retrospective study was performed on 17 patients who were diagnosed with PSV by color Doppler ultrasound in the Second Hospital of Shandong University and the Shandong Provincial Hospital Affiliated to Shandong First Medical University from May 2010 to December 2021. Their sonographic features were analyzed, summarized and classified.Results:In all the 17 cases, the sciatic vein showed a vein adjacent to the sciatic nerve in the pelvis or back of the thigh. According to anatomy, persistent sciatic vein could be divided into three types: complete PSV, upper PSV and lower PSV. There were 7 cases of complete PSV, 2 cases of upper PSV and 8 cases of lower PSV. Femoral vein dysplasia was found in 11 of 17 patients with PSV. In addition to 1 case of bilateral PSV, the diameter of the femoral vein on the affected side was (0.36±0.19)cm in 16 cases, and the diameter of femoral vein at the corresponding position on the healthy side was (0.61±0.11)cm, there was significant difference between the two groups ( P<0.001). Conclusions:Color Doppler ultrasonography is the effective imaging method for diagnosis of the PSV.