〔Abstract〕 Objective To analyze the role of placental pathology in obstetrics subclinical infection. Methods A total of 200 cases of parturient women undergoing natural vaginal delivery in Shaoguan First People's Hospital from January 2019 to December 2020 were selected as the research object. The first 100 parturient women admitted to hospital were set as the control group and none of them underwent placental pathological examination, while the latter 100 parturient women were set as the observation group and all of them received placental pathological examination. Maternal and neonatal infection rates were compared between the two groups. Results The proportion of pelvic infection and wound infection in the control group was 5% and 8%, respectively, and the total infection rate was 13%. The observation group was 2% and the total infection rate was 4%, and the difference was statistically significant (P < 0.05). The proportion of neonatal pneumonia and septicemia in the control group was 4% and 7%, respectively, and the total infection rate was 11%, while the fetal infection rates in the observation group were 1% and 2%, respectively, and the total infection rate was 3%. The difference was statistically significant (P < 0.05). Conclusion Placental pathological examination of natural vaginal delivery can effectively reduce maternal pelvic infection and wound infection rate, reduce fetal pneumonia and septicemia.