To assess associations between home indoor air environments and asthma,allergies and pneumonia,children aged 1–8 years were surveyed from 12 kindergartens in the city of Xi’an.2,020 questionnaires were responded with a response rate of 83.5%.The prevalences of doctor diagnosed asthma,hay fever,and pneumonia were 2.9%,3.6%,and 28.3%,respectively.Living close to a highway was a risk factor for current rhinitis(AOR 1.5,95%CI 1.2–1.8),eczema(AOR 1.7,95%CI 1.2–2.5),and diagnosed pneumonia(AOR 1.3,95%CI 1.0–1.6).Dampness problems in the home were associated with 50%–130%increases in the prevalences of asthma and allergy.Airing bed linen under sun-shine was protective,especially against rhinitis.Pet avoidance was consistently and significantly associated with asthma and allergy(AOR 1.3–2.4).Decoration of the home during children’s early life is a risk factor for current rhinitis(AOR 1.9,95%CI 1.3–2.9)and eczema(AOR 1.9,95%CI1.1–3.6).Risk factors for pneumonia were living in an apartment(AOR 1.4,95%CI 1.1–1.8),latex wall paint(AOR 1.3,95%CI 1.0–1.7),dampness(AOR 1.4–1.5),breast feeding3 months(AOR 1.3,95%CI 1.0–1.7),never airing bed linen in sunshine(AOR 1.3,95%CI1.3–1.6),and cleaning children’s room less frequently than once per day(AOR 1.4,95%CI 1.1–1.7).This study demonstrates that home indoor environmental and life style factors may influence the health of children in Xi’an. To assess associations between home indoor air environments and asthma, allergies and pneumonia, children aged 1-8 years were surveyed from 12 kindergartens in the city of Xi’an. 2,020 questionnaires were responded with a response rate of 83.5%. The prevalences of doctor diagnosed asthma, hay fever, and pneumonia were 2.9%, 3.6%, and 28.3%, respectively.Living close to a highway was a risk factor for current rhinitis (AOR 1.5, 95% CI 1.2-1.8), eczema (AOR 1.7, 95% CI 1.2-2.5), and diagnosed pneumonia (AOR 1.3, 95% CI 1.0-1.6). Dampness problems in the home were associated with 50% -130% increases in the prevalences of asthma and allergy. Airing bed linen under sun -shine was protective, especially against rhinitis. Pet avoid was was and significantly associated with asthma and allergy (AOR 1.3-2.4) .Decoration of the home during children’s early life is a risk factor for current rhinitis (AOR 1.9, 95% CI 1.3 -2.9) and eczema (AOR 1.9, 95% CI 1.1-3.6) .Risk factors for pneumonia were living i latex wall paint (AOR 1.3, 95% CI 1.0-1.7), dampness (AOR 1.4-1.5), breast feeding 3 months (AOR 1.3, 95% CI 1.0-1.7), never airing bed linen in sunshine (AOR 1.3, 95% CI 1.3-1.6), and cleaning children’s room less frequently than once per day (AOR 1.4, 95% CI 1.1-1.7). This study demonstrates that home indoor environmental and life style factors may influence the health of children in Xi’an.