Abstract: Objective: To investigate the CT and MRI features of undifferentiated embryosarcoma(UESL) of the liver in adults. Materials and methods: the clinical and imaging data of 5 patients with ueslwere analyzed retrospectively. Results: the lesions were single in 5 cases, 4 in the right lobe of the liver and 1 in the left and right lobe of the liver. CT/MRI showed a solid mass with fuzzy boundary, nodular and irregular soft tissue density/signal shadow on the wall of the cyst, uneven separation of thick wall, low density on CT plain scan, large liquefaction and necrosis on MRI plain scan, long T1 and long T2 signal changes on MRI plain scan, and slightly progressive enhancement on CT/MRI enhanced scan of wall nodule, soft tissue composition and separation in the cyst. Conclusion: the imaging findings of adult UESL have certain diagnostic value, which is helpful for preoperative diagnosis.