Abstract: Objective To analyze the value of neutrophils to lymphocytes(NLR)ratio, platelets to lymphocytes(PLR)ratio and platelet count(PLT)in diagnosis of preeclampsia(PE). Methods The clinical data of 137 pregnant women(experimental group)who were formally established cards in our hospital and diagnosed as PE in the late pregnancy and 130 healthy pregnant women(control group)who were formally established cards in the same period was analyzed retrospectively. PLR, NLR and PLT were compared between the experimental group and the control group. Results The level of NLR in the experimental group was significantly higher than that in the control group, the level of PLR was significantly lower than that in the control group(P<0.05); the levels of PLT and PLR in the severe PE group were significantly lower, and the level of NLR was significantly higher than that in the mild PE group(P<0.05). Logistic regression analysis showed that PLR and NLR were independent predictors of PE(P<0.001). The time from onset of high blood pressure to termination of pregnancy were negatively correlated with NLR(r=-0.173, P=0.043), and positively correlated with PLT(r=0.241, P=0.005). Conclusion The occurrence and progress of PE can be predicted by monitoring the changes of NLR, PLR and PLT during pregnancy.