Abstract:〔Abstract〕 Objective To investigate the diagnostic value of transvaginal real-time four-dimensional fallopian tube contrast ultrasonography (RT-4D-HyCoSy) combined with transvaginal three-dimensional ultrasound (3D-TVS) in infertile female patients with tubal permeability. Methods A total of 242 fallopingtubes were diagnosed in 121 infertile patients admitted to Fuzhou Jiahe Jiamei Hospital from November 2020 to November 2021. All patients underwent laparoscopic fluidectomy, RT-4D-HyCoSy and 3D-TVS. The results of laparoscopic fluidectomy were considered as the "gold standard". The diagnostic results and diagnostic efficacy of RT-4D-HyCoSy and 3D-TVS alone and in combination for tubal obstruction in infertile patients were compared. The detection rate of tubal permeability was examined by the two methods alone and in combination, and the adverse reactions of RT- 4D-HyCoSy were analyzed. Results The results of laparoscopy showed that 54 of 242 fallopian tubes were obstructed, of which 86 were obstructed and 102 were unobstructed. Compared with RT-4D-HyCoSy and 3D-TVS alone, RT-4D-HyCoSy combined with 3D-TVS had higher diagnostic sensitivity of 90.74%, higher accuracy of 96.69%, and lower missed diagnosis rate of 9.26%, with statistically significant differences (P < 0.05). Compared with RT-4D-HyCoSy and 3D-TVS alone, the detection rate of tubal permeability was higher by combined examination, and the difference was statistically significant (P < 0.05). The incidence of adverse reactions in RT-4D-HyCoSy was 8.26% (10/121) lower than 20.66% (25/121) of the laparoscopy, and the difference was statistically significant (P < 0.05). Conclusion The diagnostic value of RT-4D-HyCoSy combined with 3D-TVS examination is significantly higher than that of single examination, which can effectively improve the diagnostic efficiency and detection rate of tubal permeability, and has important significance for early clinical diagnosis and treatment planning.