Objective:To investigate the relationship between peripheral blood neutrophil/lymphocyte ratio(NLR),platelet/lymphocyte ratio(PLR)and pertussis pneumonia in children and their clinical significance.Methods:A total of 59 cases of pertussis pneumonia and 99 cases of non-pertussis pneumonia diagnosed in the hospital from August 2021 to July 2022 were selected as research objects.The neutrophils count,lymphocyte count and platelet count in peripheral blood were recorded during the initial routine blood transfusion.The difference of NLR and PLR between the pertussis group and the control group was compared by t test.The critical value of NLR and PLR in pertussis pneumonia was determined by Receiver Operating Characteristic curve(ROC curve).Results:The lymphocytes and platelets in whole blood of pertussis group and PLR were higher than those in control group.C-reactive protein were lower than those in control group(P<0.05).The optimal cut-off values oflymphoid cells,PLR,NLR and CRP were 4.02,6704.29,181.16 and 1.89,respectively.The sensitivity of diagnosis was the highest in PLR(82.8%),and the specificity was the highest in NLR(86.4%).Conclusion:The combined determination of NLR,PLR and the four indexes has important reference significance in the differentiation of pertussis pneumonia and non-pertussis pneumonia.