【】 Objective To explore the diagnostic value of three-dimensional overcast ultrasonography in the abnormal position of intrauterine device.Methods During the period from January 2014 to December 2017, 113 patients with abnormal position of IUD were enrolled in this study.They were performed two-dimensional ultrasound, three-dimensional ultrasound, three-dimensional ultrasound combined tomography examination.Laparoscopic or hysteroscopic surgery results for the "gold standard", compared with three diagnostic methods for diagnosis of intrauterine device position abnormalities accuracy.Results Compared with the results of surgery, the accuracy of three-dimensional ultrasonography combined with tomography in diagnosis of different types of IUDs was the highest, and the diagnostic accuracy of IUDs down and deformation was significantly higher than that of two-dimensional ultrasound with statistical differences Significance of learning (P <0.05).Compared with the surgical results, in 113 cases of intrauterine device position abnormalities, 73 cases were diagnosed by two - dimensional ultrasonography and the diagnostic accuracy was 64.60%.Ninety - three cases were diagnosed by three - dimensional ultrasonography and the diagnostic accuracy was 87.61%.111 cases were diagnosed by three-dimensional ultrasonography combined with tomography, the diagnostic accuracy was 98.23%.The accuracy of three-dimensional ultrasonography combined with tomography in the diagnosis of IUD abnormalities was statistically different from that of two-dimensional ultrasound and three-dimensional ultrasound (P<0.05).Conclusions Three-dimensional combined with ultrasonography can clearly and completely show the shape of intrauterine devices, and help to improve the diagnostic accuracy of intrauterine device position abnormalities, worthy of clinical application.