Transvaginal ultrasound (TVS) is generally considered superior to transabdominal ultrasound (TAS) in the estimation of endometrial abnormalities. A disadvantage of TVS is the limited field of view. The purpose of this study is a comparison between TAS and TVS for endometrial cancer screening. Ninety-one postmenopausal women were included. They were evaluated by TAS, TVS, and endometrial tissue sampling. The mean endometrial thickness estimated by TVS was larger than that obtained by TAS (p < 0.0001). Sensitivity and specificity of TAS were 83.3 and 58.8% and of TVS 100 and 54.1%, respectively. We conclude that TVS might be superior to TAS, especially in patients with a retroflexed uterus.