We investigated the relationship between indoor air pollution and the risk of childhood acute leukemia (AL).A community-based case-control study was conducted in Shanghai between April 2011 and January 2014, 97 cases aged<15,diagnosed with AL and 148 controls matched for age, gender and residence were enrolled.Questionnaire data was obtained, and quantitative measurements of indoor air were taken with passive samplers and analyzed by GC/MS.Higher concentrations of chlorinated hydrocarbons were observed in cases than in controls and were significantly increased the risk of childhood AL (OR=2.42, 95%CI=1.11-5.31).For the individual components, higher concentrations of butyl alcohol (OR=1.82,95%CI=1.04-3.21) and 1,2-dichloroethane (OR=1.80, 95%CI=1.02-3.19) were observed to be associated with an increased risk of childhood AL.The increased AL risk among children with higher concentrations of pollutants in their bedrooms suggests that indoor air pollution may be associated with the risk of childhood AL.