Abstract: OBJECTIVE To explore the relationship between the risk of recurrent respiratory tract infection（RRTI） and the disease development and polymorphisms of matrix metalloproteinase-1（MMP1） and tissue inhibitor of metalloproteinase-1（TIMP1） genes. METHODS During the period from May 2016 to Dec 2019, 82 children with RRTI and 60 healthy children who underwent physical examination in Chaoyang Central Hospital were enrolled. The polymorphisms of MMP1（-1607 locus） and TIMP1（-372 locus） genes were detected by polymerase chain reaction-restriction fragment length polymorphism, and the relationship between different genotypes and RRTI was analyzed. The peripheral blood levels of MMP1 and TIMP1 were detected by enzyme-linked immunosorbent assay. The predictive value of serum MMP1 and TIMP1 for RRTI was analyzed. RESULTS Passive smoking, picky eater and taking antibiotics more than 7 times/year were the independent risk factors for RRTI（P＜0.05）. MMP1 and TIMP1 levels in the RRTI group were significantly higher than those in the control group（P＜0.05）. The receiver operating characteristic（ROC） curves analysis showed that area under the ROC curve（AUC） values of serum MMP1 and TIMP1 levesls were 0.766（95% confidence interval: 0.686-0.846） and 0.784（95% confidence interval: 0.704-0.863）, respectively. There were significant differences in the distribution of MMP1 genotype（-1607 locus） between the two groups（P＜0.05）. Compared with control group, the frequency of 2 G allele at MMP1（-1607 locus） in the RRTI group was significantly increased（P＜0.05）. There was no significant difference in the distribution of TIMP1（-372 locus） genotype between the two groups; while compared with control group, the frequency of C allele at TIMP1（-372 locus） in the RRTI group was significant higher（P＜0.05）. CONCLUSION 2 G allele at MMP1（-1607 locus） and C allele at TIMP1（-372 locus） are risk factors of RRTI. The passive smoking, picky eating and taking antibiotics will increase the risk of RRTI. Clinically, targeted management measures should be performed to prevent RRTI effectively.