Background: Endometrial and sub-endometrial lesions are common cause of abnormal uterine bleeding (AUB). Ultrasound is a reliable diagnostic tool for those lesions, but not all patients exhibit definite changes in ultrasound. Elastography, as shear wave elastography (SWE), can assess the mechanical properties of the endometrial lesions and provides quantitative measure of tissue stiffness.Our study aimed to determine the added value of SWE in diagnosis of different lesions. Methods: Thirty-six patients presented by AUB with pathologically proven endometrial and sub-endometrial pathologies were included in this prospective study and assessed with transvaginal SWE. The mean elasticity values (E mean) in Kilopascals (KPa),and the ratio of the mean elasticity of the lesion to the mean myometrial elasticity (E/M ratio) were calculated in variable lesions. Results: There was statistically significant difference in the E mean (P >0.001) also the E/M ratio of different endometrial and sub-endometrial lesions (P >0.0001). E mean value in endometrial carcinoma (EC) was 39.79 ± 3.65,endometrial hyperplasia (EH) was 24.24 ± 1.52, and endometrial polyp was 15.74 ± 2.71. While that of submucosal fibroid was 59.36 ± 12.84 and adenomyoma (AM) was 52.15 ± 4.44. In the analysis of subgroups, the E/M ratio of uterine polyp (0.36 ± 0.07) was statistically significantly lower than other subgroups (P >0. 1), while submucosal leiomyoma (1.8 ± 0.27) and focal adenomyoma (1.37 ± 0.07) had significantly higher values than other subgroups (P >0. 1). Conclusions: SWE is an effective additional method in differentiating between benign and malignant lesions when combined with conventional ultrasonography.