OBJECTIVE: By the use of three-dimensional ultrasound in patients before and after radical hysterectomy surgery, in order to assess the changes of pelvic floor morphological and anatomy . METHODS: There were 45 cases had radical hysterectomy due to uterine lesion , and the parameters were measured in the preoperative one day and fourteen days after surgery by application of three-dimensional ultrasound through the perineum volume scanning, three-dimensional ultrasound image reconstruction, observed levator hiatus structure and anatomy, and the parameters including levator hiatus anteroposterior diameter, diameter, area, and levator ani muscle thickness during quiescent period and pressure period(when Valsalva breathing). RESULTS: The anatomy of the pelvic floor changed with patients after radical hysterectomy, the levator hiatus anteroposterior diameter, diameter, area were slightly increased and levator ani muscle thickness were slightly reduced during quiescent period, but the difference was not statistically significant (P> 0.05); compared the quiescent period, the levator hiatus anteroposterior diameter, diameter and area increased during Valsalva breathing with preoperative patients, the difference was statistically significant (P <0.05), levator ani muscle thickness were slightly reduced, but the difference was not statistically significant (P> 0.05); compared the quiescent period, the levator hiatus anteroposterior diameter, diameter and area increased during valsalva breathing with postoperative patients, levator ani muscle thickness were slightly reduced, and the difference was not statistically significant (P> 0.05).CONCLUSION: Ultrasound can be used to the hysterectomy surgery for morphological changes of the female pelvic floor dynamic observation, objective evaluation of changes in its anatomy.