Whether indoor environmental smoke is harmful for preschool children’s respiratory health in a society where female smoking is rare has not been determined.This study is part of a cross-sectional study(CCHH study-phase one in Shanghai)and investigated associations between parental smoking and incense-burning and respiratory symptoms among 4–6 year old children in Shanghai,China.A number of 13335 valid questionnaires(response rate:85.3%)were analyzed.A number of 56.1%(as reported by a parent)of preschool children in Shanghai are exposed to environmental tobacco smoke(ETS).A number of 40.3%of fathers and0.9%of mothers are smokers.A number of 53.7%and 12.6%of Shanghai residents have used mosquito-repellent incense and incensation respectively.Children exposed to any parental smoking have higher prevalence of wheeze and croup than those not exposed.Current maternal smoking has a significant and positive association with wheeze(in the last 12 months,AOR,95%CI:1.83,1.11–2.99).However,paternal smoking either currently or at child’s birth had only weak associations with wheeze and croup.Incense-burning(mosquito-repellent incense and incensation)had significant and negative association with doctor-diagnosed asthma(AOR,95%CI:0.85,0.73–0.99)and hay fever(AOR,95%CI:0.80,0.70–0.93).The results indicate that maternal smoking perhaps is a stronger risk factor for children’s respiratory health than paternal smoking. Whether indoor environmental smoke is harmful for preschool children’s respiratory health in a society where female smoking is rare has not been determined. This study is part of a cross-sectional study (CCHH study-phase one in Shanghai) and for associations between parental smoking and A number of 13335 valid questionnaires (response rate: 85.3%) were collected. A number of 56.1% (as reported by a parent) of preschool children in A number of 40.3% of fathers and 0.9% of mothers are smokers. A number of 53.7% and 12.6% of Shanghai residents have used mosquito-repellent incense and innsation respectively. Childrens exposed to any parental smoking have higher prevalence of wheeze and croup than those not exposed. Current maternal smoking has a significant and positive association with wheeze (in the last 12 months, AOR, 95% CI: 1.83,1.11-2.99) .However, p aternal smoking either currently or at child’s birth had only weak networks with wheeze and croup. Information-burning (mosquito-repellent incense and inception) had significant and negative association with doctor-diagnosed asthma (AOR, 95% CI: 0.85,0.73-0.99 ) and hay fever (AOR, 95% CI: 0.80, 0.70-0.93). The results indicate that maternal smoking maybe is a stronger risk factor for children’s respiratory health than paternal smoking.