Objective To investigate the diagnostic value and clinical significance of neutrophil-lymphocyte ratio (NLR), platelet-lymphocyte ratio (PLR) and lymphocyte-monocyte ratio (LMR) in children with bronchial asthma.Methods A total of 182cases newly diagnosed with asthma were divided into mild persistent group (68cases), moderate persistent group (63cases) and of severe persistent group (51cases), and 100ageand sex-matched pediatric healthy children at the same period were chosen as healthy control group.WBC, NEU, LYM, MON, EOS, PLT, IgE, NLR, PLR and LMR of all subjects enrolled in this research were retrospectively reviewed.Results There was no significant difference in age and sexuality between children with asthma and control group (P＞0.05), but WBC, EOS, NEU, MON, PLT and IgE were all significantly up-regulated, and LYM was down.NLR and PLR were significantly up-regulated in children with asthma, while LMR decreased significantly.The area under the curve (AUC) of ROC curve was 0.88and the cutoff value were 2.619for NLR in diagnosing asthmatic children.The diagnostic value of PLR was similar to that of NLR, the AUC of ROC value was 0.87, and the cutoff value was 111.1.The diagnostic value of LMR was only0.79, and the cutoff value was 5.093.In addition, there was a significant correlation between NLR and IgE or lung function indexes.PLR was also correlated with IgE, but only negatively correlated with lung function indexes such as FVC, FEV1and FEV1/FVC％.There was no significant correlation between LMR and all indexes.NLR and PLR were significantly decreased in children with severe asthma after treatment with budesonide, while LMR was significantly up-regulated.Conclusion There are abnormal changes in NLR, PLR and LMR in children with bronchial asthma, which can be used as an index for auxiliary diagnosis, disease assessment and therapeutic effect monitoring in children with bronchial asthma.