Abstract: OBJECTIVE To explore the expression changes of nucleotide binding oligomerization domain-like receptor 3（NLRP3） pathway related proteins in premature rupture of membranes（PROM） pregnant women, and to analyze its relationship with histological chorioamnionitis（Chorioamnionitis, CA）. METHODS The PROM women who were admitted to the department of Obstetrics and Gynecology of Hainan Western Central Hospital from Aug 2019 to Aug 2020 were recruited as the research subjects. According to whether CA was the combined infection, 80 cases of pregnant women were randomly divided into the CA group and non-CA group. Sixty healthy full-term pregnant women in the same hospital who gave birth under the obstetric examination during the same period were in the control group. Real-time fluorescent quantitative polymerase chain reaction（RT-PCR） was used to detect the mRNA relative expression of NLRP3 and Casepase-1 genes; cord blood specimens were collected and used to detect cord blood inflammatory factors interleukin-1β（IL-1β） and interleukin-18（IL-18） by enzyme-linked immunosorbent assay（ELISA）. RESULTS The peripheral blood NLRP3, Casepase-1 mRNA and cord blood IL-1β and IL-18 levels in the CA group were significantly higher than those in the non-CA group and the control group（P＜0.05）. The mRNA levels of NLRP3, Casepase-1 in peripheral blood and cord blood IL-1β and IL-18 levels in the non-CA group were significantly higher than those in the control group（P＜0.05）. The levels of peripheral blood NLRP3, Casepase-1 mRNA and cord blood IL-1β and IL-18 levels in pregnant women with preterm PROM were significantly higher than those in term PROM women,（P＜0.05）. ROC analysis showed that the area under the curve（AUC） of NLRP3, Casepase-1 mRNA, IL-1β and IL-18 levels for the diagnostic value of PROM with CA were 0.701, 0.735, 0.744, 0.786, respectively; the differences between them were significant（P＜0.05）. The levels of NLRP3, Casepase-1 mRNA and cord blood IL-1β and IL-18 in in the neonatal group with adverse outcome were higher than those in the neonatal group without adverse outcome, and the difference between them was significant（P＜0.05）. The correlation analysis showed that the mRNA expression of NLRP3 was positively related with Casepase-1 mRNA, IL-1β and IL-18 levels（P＜0.05）. CONCLUSION Proteins in the NLRP3 pathway are significantly up-regulated in PROM patients with CA, which may participate in the progression of inflammation and are related to adverse neonatal outcomes.