OBJECTIVESThis study investigated the association between allergen sensitization and current asthma in children in the United States using data from the 2005-2006 National Health and Nutrition Examination Survey (NHANES).METHODSChildren who participated in the 2005–2006 NHANES, aged 6 years to 19 years, were included in this study. A structured questionnaire was used to assess asthma status (without asthma, asthma in remission, or current asthma). Nineteen specific immunoglobulin E (sIgE) levels were measured using the Pharmacia Diagnostics ImmunoCAP 1000 System (Kalamazoo, MI, USA). A machine-learning method was applied to select important sIgEs related to childhood asthma. Multivariate regression analysis was used to test this hypothesis.RESULTSIn total, 2,875 children were recruited. The prevalence of ever having asthma and current asthma was 16.5% and 5.6%, respectively. Six sIgE levels were found to contribute to asthma using bootstrap forest selection. After adjusting for the child’s sex, age, and family income, children with double the sIgE levels ofDermatophagoides farinae, dogs, andAspergilluswere more likely to have current asthma than children without asthma (odds ratio [95% confident interval]: 1.11 [1.04 to 1.19], 1.30 [1.16 to 1.46], and 1.55 [1.39 to 1.72], respectively).CONCLUSIONSOur findings suggest that allergen sensitization, especially toAspergillus, is associated with current asthma in children. Strategies to reduce sensitization may help prevent and manage asthma.