Microbiome of female reproductive system are closely related to female reproductive health. Vaginal microbial flora changes are associated with a variety of vaginal diseases and may inflect the uterus through the cervix, inflammatory response in the uterus during pregnancy can lead to preterm birth (preterm birth, PTB). PTB is defined as a delivery that occurs at 28 weeks but less than 37 weeks of gestation, PTB infant mortality rate is very high and is faced with a variety of health-disease, in addition to clear the infection of pathogenic microorganism, PTB accompanied by microbiome imbalances in reproductive system, it is hoped that PTB can be prevented according to the dynamic changes of female reproductive system microbiome in the future. This review will focus on the relationship between the female reproductive system microbiome and reproductive health, especially with PTB.