Objective To comparatively analyze the value of transvaginal ultrasonography and magnetic resonance imaging (MRI) in the diagnosis of endometrial carcinoma. Methods 70 patients with pathologically confirmed endometrial carcinoma treated in our hospital from January 2014 to August 2017 were selected. They were examined by transvaginal ultrasonography and MRI before operation, and imaging findings were observed. With pathological results as the standard, the sensitivities and accuracies of transvaginal ultrasonography and MRI in diagnosis of preoperative stage were comparatively analyzed. Results Transvaginal ultrasonography detected that there were 41 cases at stage I, showing endometrial thickening, strong internal echo or uneven echo, 21 cases at stage II showing endometrial extension mass shadow, and 8 cases at stage III showing incomplete perimetrium or adnexal mass shadow. MRI detected that there were 41 cases at stage I showing intimal thickening and complete outline of myometrium, 22 cases at stage II showing cervical invasion and internal low signal, and 7 cases at stage III showing persistent interruption signal of external myometrium or invasion near the uterus. With operation and pathology as the standard, the accuracy of transvaginal ultrasonography in staging endometrial carcinoma was 87.14%, compared with 91.43% of MRI, there was a statistically significant difference (P<0.05). Conclusion Transvaginal ultrasonography and MRI are of great significance in the diagnosis of endometrial carcinoma before operation.