Objective To investigate and analysis the CT and MRI features of uterine carcinosarcoma and to promote diagnostic accuracy of the disease. Methods Clinical data, CT and MR imagings of 17 uterine carcinosarcoma patients confirmed by pathology were reviewed and analyzed retrospectively. Results All the cases presented with two patterns, type I showed large irregular or round-like mass occurred in uterine cavity or cervical canal (n=7), type II showed polypoid or irregular smaller lumps, or simple endometrial thickening, which were similar to endometrial carcinoma(n=10). The radiographic features are as follows: ⑴moderate density on plain CT scans, isointensity or sometimes mixed signal intensity on unenhanced T1-weighted imagings and intermediate or heterogeneous signal intensity on T2-weighted images; the disappearance or discontinuity of junctional low-intensity band on T2-weighted imagings indicating myometrium invasion, ⑵common hypointense or low-density relative to adjacent myometrium on contrastenhancement imagings, ⑶heterogeneous hyperintensity on diffusion-weighted imagings with higher mean ADC value of (1.02±0.3)×10-3mm2 /s, ⑷intratumoral flow voids and cystic necrosis likely to be found. Conclusion Characteristics of uterine carcinosarcoma including patterns of the tumor, intratumoral flow voids and higher ADC values will do help in differential diagnosis with endometrial carcinoma. MRI is of great significance in diagnosis of intratumoral hemorrhage and cystic necrosis, as well as assessment of the depth of tumor invasion.