Objective To investigate the impact of eotaxin-3 gene polymorphisms on the clinical effect of inhaled corticosteroids (ICS) to provide clinical basis for eotaxin-3 as the target spot for treating bronchial asthma.Methods One hundred and ninety-six cases of asthma and 196 cases as controls were selected from the outpatients and inpatients in our hospital.Peripheral blood samples were collected from the asthma patients and normal controls.PCR-RFLP was adopted to detect the genotypes of eotaxin-3 +2497T＞G and-+-77C＞T.The response of ICS treatment and the change situation of ACT scores were compared among asthmatic patients with various genotypes.Results Peripheral blood eosinophil(EOS) counts,EOS proportion and total IgE in the patients with TG genotype at+2497 locus were significantly decreased compared with those in the patients with TT genotype,the difference was statistically significant(P＜0.05).The level of PD20 in asthmatic patients with TG genotype was significantly higher than that in the patients with TT genotype,the difference was statistically significant[(0.07-±-0.03)mg vs.(0.03 ± 0.01)mg,t=2.45,P=0.048];whereas the above indicators had no statistical difference among 3 kinds of +-77 genotypes.During ICS treatment process in the patients with TT genotype at +-2497 locus,the FEV1％,PD20 value and ACT scores were significantly improved compared with those in the patients with TG genotype,the difference was statistically significant(P＜0.01).Conclusion The asthmatic patients with TT genotype at +-2497 locus were more sensitive to ICS treatment,regular ICS treatment can significantly improve the lung function and clinical symptom score in these patients.