Objective To explore the natural recovery of pelvic floor function and its influencing factors in primiparas. Methods From May 2018 to May 2024，189 primiparas received follow-ups at 6 weeks，12 weeks，and 1 year postpartum in Shijiazhuang No.4 Hospital. Their general conditions，obstetric conditions， and manual muscle strength，electrophysiological indicators of pelvic floor and pelvic organ prolapse classification at three time points of follow-up were collected. Chi-square test and generalized estimating equations （GEE） were used to analyze influencing factors of pelvic floor muscle strength. Results No significant difference was found in the detection rate of abnormal pelvic floor muscle strength （Grade 0-2） at 6 and 12 weeks postpartum，but the abnormal rate at 1 year was significantly higher. GEE showed that 1 year postpartum，voluntary pelvic floor muscle exercise，physical labor intensity，and fetal weight significantly affected pelvic floor function （P<0.05）； the 1 year postpartum，physical labor intensity and fetal weight were risk factors，while voluntary pelvic floor muscle exercise was a protective factor. Conclusions In natural recovery state， the incidence of abnormal pelvic floor muscle strength in primiparas increases with postpartum time. Voluntary pelvic floor muscle exercise improves pelvic floor function，while 1 year postpartum，physical labor intensity，and fetal weight are risk factors for pelvic floor muscle strength.