Abstract:【Abstract】 Objectives To investigate the value of ultrasonographic elastography in the differential diagnosis of benign and malignant pelvic masses of Gynecologic Imaging Reporting and Data System 4 (GIRADS 4 ).Methods Color Doppler ultrasonography was performed on 185 pelvic masses,and the findings were classified by the Gynecologic Imaging Reporting and Data System (GIRADS). Transvaginal ultrasonographic elastography was used on 22 lesions which were classified to GIRADS 4 (probably malignant). The elasticity color code (pattern 15) were compared with final pathological results.Results 14 benign lesions (elasticity color pattern 12) and 8 malignant lesions (elasticity color pattern 35) were finally diagnosed. There were statistically difference between benign lesions and malignant lesions in elastic scores (P<005).The sensitivity, specificity, positive predictive value and negative predictive value of ultrasound elasticity imaging were 875%, 857%, 778% and 923%, respectively, and the accuracy was 864%. Conclusion Transvaginal ultrasonographic elastography has widely application prospect in the differential diagnosis of benign and malignant pelvic masses which were classified into GIRADS 4