Endometrial cancer (EC) is the fourth most commonly diagnosed malignancy in the world. The first symptom of endometrial carcinoma usually is postmenopausal bleeding, but only about 10–15% of women presenting with postmenopausal bleeding will actually have EC, and a definitive diagnosis needs histological proof. Ultrasonography is a useful tool for detecting endometrial pathology in everyday practice. To optimize the sonographic assessment of endometrial tumors, a better understanding of the association between sonographic features and tumor stage, grade, and histological type is needed. Three-dimensional (3D) ultrasonography is a new imaging technique that has become currently available in gynecologic practice, specifically in gynecologic oncology. In addition, 3D/four-dimensional (4D) power Doppler ultrasonography allows a 3D reconstruction of the vascular network and also calculates vascular indices based on the total and relative amount of power Doppler information within the volume of interest. Accurate clinical staging of EC not only reduces complications caused by inadequate or overtreatment but is also a guarantee for the retention of fertility in young patients.