Abstract: Objective：To explore the clinical features, treatment, and prognosis of undifferentiated embryonal sarcoma of liver. Methods：The clinical data of 17 patients with undifferentiated embryonal sarcoma of liver were collected and retrospectively analyzed. Results：Among the 17 patients, there were 10 males and 7 females, aged from 11 to 66 years (median age was 47 years). The main clinical manifestations were abdominal mass, accompanied by abdominal pain and distension. The median diameter of the tumors was 13 cm (6.5-40 cm). Among the 17 patients, 15 patients underwent surgical operation, among whom 8 patients were treated by operation alone, 1 patient was treated by operation plus transcatheter arterial chemoembolization (TACE), 2 patients were treated by operation plus chemotherapy, 4 patients were treated by operation plus chemotherapy, and another 2 patients were treated by TACE alone. The median follow-up time was 11 months (1-60 months) for the 17 patients, 2 patients were lost, and 1 patient had recurrence. The overall 1-year survival rate was 42.9% (6/14) and the 2-year survival rate was 28.6% (4/14). Among the 6 patients who received combined chemotherapy after operation, 1 patient had no relapse during the 7 months of follow-up, 3 patients had partial remission, 2 patients had disease progression, and all the 6 patients had grade 4 bone marrow depression. Conclusions：Undifferentiated embryonal sarcoma of liver is a rare tumor, with a large intrahepatic lesion and high recurrence and metastasis rates. The combined treatment of operation, interventional chemoembolization, and chemotherapy may improve the overall survival, but the prognosis is still relatively poor.