Abstract: OBJECTIVE To analyze the influencing factors for puerperal infection in patients with premature rupture of membranes（PROM） and observe the predictive value of Toll like receptor 4（TLR4） in placenta and fetal membrane tissues. METHODS A total of 88 patients with PROM who were treated in the obstetrics department of Zibo First Hospital from May 2016 to May 2020 were recruited as the study subjects and divided into the infection group and the no infection group according to the status of puerperal infection. The related factors for puerperal infection and expression levels of TLR4 in placenta and fetal membrane tissues were observed, and the value of placenta and fetal membrane tissues TLR4 expression level in diagnosis of puerperal infection was analyzed by using receiver operating characteristic（ROC） curve. RESULTS Totally 14 patients had puerperal infection, with the infection rate 15.91%. The proportions of the patients with gestational age less than 37 weeks, prenatal anemia, gestational diabetes mellitus, history of genital tract infection, time of rupture of membranes no less than 12 hours, and postpartum hemorrhage were significantly higher in the infection group than in the no infection group（P＜0.05）.The result of multivariate logistic regression analysis showed that the incidence of puerperal infection in the PROM patients was associated with the gestational age, the less than 37 weeks of gestational age could increase the risk of puerperal infection（P＜0.001）. The expression level of TLR4 in placenta and fetal membranes was significantly higher in the infection group than in the no infection group（P＜0.05）. There was significant difference in the area under curve（AUC） of ROC of the placenta and fetal membrane tissues TLR4 expression level in prediction of puerperal infection（P＜0.05）, under cutoff value, the sensitivity and specificity were respectively 0.643 and 0.714, 1.000 and 0.986. CONCLUSION The PROM patients with puerperal infection may have the up-regulation of TLR4 in placenta and fetal membranes tissues, and the index may facilitate the prediction of risk of puerperal infection and early diagnosis.