Objective To explore the diagnostic value of shear wave elastography (SWE) combined with four-dimensional pelvic floor ultrasound for pelvic floor dysfunction (PFD) after total hysterectomy.Methods A total of 156 patients who underwent total hysterectomy at our hospital from January 2021 to January 2023 were included in the study. According to postoperative follow-up results, 64 patients with PFD were assigned to the observation group, and 92 patients with normal pelvic floor function were assigned to the control group. All patients underwent re-examination at 4 weeks after surgery. Pelvic floor ultrasound was used to assess the cervical external os descent (COD), urethral rotation angle (URA), bladder neck descent (BND) during both resting and Valsalva maneuvers. SWE was used to measure the levator hiatus area (LHA) and the Young’s modulus of the puborectalis muscle during both resting and Valsalva maneuvers. Logistic regression analysis was performed to determine the associations between SWE and four-dimensional pelvic floor ultrasound findings and PFD, and receiver operating characteristic (ROC) curves were applied to evaluate the diagnostic efficacy of four-dimensional pelvic floor ultrasound and SWE for postoperative PFD.Results The COD, URA, and BND values in the observation group were significantly higher than those in the control group both at rest (P < 0.05) and during Valsalva maneuvers (P < 0.05). The LHA values in the observation group were also higher than those in the control group both at rest and during Valsalva maneuvers (P < 0.05), while the Young's modulus values in the observation group were lower than those in the control group (P < 0.05). Multivariate Logistic regression analysis revealed that higher values of COD [O^R = 1.789 (95% CI: 1.287, 2.488) ], URA [O^R = 2.264 (95% CI: 1.329, 3.856) ], and BND [O^R = 1.722 (95% CI: 1.128, 2.630) ], along with lower Young's modulus values [O^R = 0.698 (95% CI: 0.551, 0.885) ], were risk factors for post-operative PFD (P < 0.05). ROC curve analysis showed that the combined detection of COD, URA, BND, and Young's modulus during Valsalva maneuvers had an accuracy of 0.982 (0.961, 1.000) for predicting post-operative PFD, with a sensitivity of 95.3% (0.869, 0.990) and a specificity of 97.8% (0.924, 0.997).Conclusion SWE combined with four-dimensional pelvic floor ultrasound has a high diagnostic value for PFD after total hysterectomy.