Abstract:【Objective】To explore the effect of different delivery methods on pelvic floor function by pelvic floor ultrasound and pelvic floor muscle strength evaluation. 【Methods】Sixty-three cases of primipara admitted to our hospital from June 2017 to June 2018 were selected as the research object. According to different delivery methods, the puerperas were divided into cesarean section group (n=33) and natural delivery group (n=30). Another 28 women who came to our hospital for health examination in the same period were selected as the control group. The changes of pelvic floor ultrasonography and pelvic floor muscle strength evaluation indexes were compared between the two groups, and the data were compared with those of the control group. 【Results】In resting state, pelvic floor ultrasonography showed that the bladder neck angle, bladder neck mobility and bladder rotation angle of natural delivery group and cesarean section group were significantly higher than those of control group, while those of natural delivery group were higher than those of cesarean section group, the difference was significant (P<0.05). Pelvic floor muscle strength evaluation results showed that natural delivery group and cesarean section group were significantly higher than those of natural delivery group (P<0.05). The persistent contraction force and maximum contraction force of pelvic floor muscle in the uterine delivery group were lower than those in the control group, while those in the natural delivery group were lower than those in the cesarean section group, and the difference was also statistically significant (P<0.05).【Conclusion】Pelvic floor ultrasonography and pelvic floor muscle strength assessment have certain predictive value for postpartum stress urinary incontinence and organ prolapse.