BACKGROUND AND AIM: Petrochemical industrial complexes would emission s several pollutants that were associated with adverse effect in respiratory system. Aim of present study is using different surrogate indices of petrochemical exposure to evaluate the effect on childhood asthma. METHODS: We conducted a singleton birth cohort by using the 2000-2014 Taiwan Birth Certificate Database (TBCD), linked with Nation Health Insurance Research Database (NHIRD) for follow-up. The distance to the nearest petrochemical industrial parks (PIPs) and benzene exposure level were uses as surrogating petrochemical exposure indices. Exposure windows were divided into prenatal and postnatal periods. The Cox proportional hazard models were applied to evaluate the effects. RESULTS:In total, 227601 asthma cases were newly diagnosed until to 2016/12/31. Younger maternal age and greater proportions of male, preterm birth, low birth weight, delivery by Caesarean section, maternal gestational hypertension were observed for asthma children than non-asthma children. The results showed that compared with those living in the farthest, living close to PIPs (HR = 1.67, 95% CI: 1.65–1.70, for 10 km vs. ≥ 40 km) were observed to have an increased risk of asthma occurrence. Higher benzene exposure levels during prenatal or postnatal period having higher risks of asthma were also found. CONCLUSIONS:In present study, we found living near PIPs and exposure to higher level of benzene during prenatal or postnatal period would increase the risk of childhood asthma occurrence. KEYWORDS: Children's environmental health, Asthma, Chemical exposures