【Abstract】Objective: to explore the application value of gynaecological imaging report and data system (GI-RADS) in the benign and malignant differentiation of accessory tumors.Methods: a retrospective analysis was performed on 180 patients with adnary masses who underwent gynecological ultrasound examination in our hospital from November 2018 to January 2020. According to the ultrasonic characteristics of adnexal masses, they were classified by GI-RADS, and their diagnostic efficacy and optimal critical value were calculated based on the gold standard of pathological results.Results: 180 cases were malignant, 39 cases were malignant, and 141 cases were benign. In the classification of GI-RADS, 15 cases were judged as GI-RADS2, and none were malignant.There were 112 cases of GI-RADS3, 1 of which was malignant.There were 25 cases of GI-RADS4, 12 of which were malignant.There were 28 cases of GI-RADS5, 26 of which were malignant.The sensitivity, specificity and accuracy of GI-RADS5 were respectively 66.7%、98.6% and 91.7%, and that of GI-RADS4 and 5 were respectively 97.4%、89.4% and 91.1%.It is suggested that GI-RADS > 3 is the best critical value to predict malignant adnexal mass.Conclusion: the classification of GI-RADS can be better applied to the diagnosis of adnexal benign and malignant tumors. It is suggested that patients with GI-RADS4 and 5 types of tumors should be considered as adnexal malignant tumors, and its diagnostic efficacy is better.