Objective To compare the incidence of respiratory and allergic diseases in children in Xuhui District， Shanghai in 2013 and 2020， and to determine the influencing factors.

Methods Annual average levels of air pollutants including PM_2.5， PM₁₀， O₃， SO₂， and NO₂ were collected and described in Shanghai from 2013 to 2020. A cross-sectional survey was conducted by using a questionnaire among grade 3 to 5 students in a school in Xuhui District， Shanghai， in September 2013 and 2020， respectively. The questionnaire collected variables including living environment， daily habits， family history of respiratory and allergic diseases， and incidence of these diseases in children. Chi-square test was used to determine the difference across respiratory and allergic diseases. Logistic regression was conducted to determine the influencing factors.

Results A total of 1 398 valid questionnaires were collected （705 in 2013 and 693 in 2020）. Compared with 2013， annual average concentrations of PM_2.5， PM₁₀， O₃， SO₂， and NO₂ in 2020 significantly decreased. The prevalence of bronchial asthma， bronchitis， persistent cough and persistent expectoration in 2013 were significantly higher than those in 2020 （P<0.05） in Xuhui District. Multivariate analysis showed that severe air pollution， boys， parents with asthma or allergy， parents with higher educational levels， and more allergens in household were the risk factors associated with the incidence of bronchial asthma， bronchitis， allergic rhinitis and atopic eczema （P<0.05）. Parents with allergy history， high smoking frequency of family member， and more allergens in household were the risk factors associated with the incidence of persistent cough and persistent expectoration （P<0.05）.

Conclusion To 2013，2020 air pollution in Shanghai has been mitigated and prevalence of bronchial asthma and bronchitis of children has decreased. Childhood respiratory and allergic diseases are associated with indoor and outdoor environment， family medical history， and family daily habits.