Background: Adenoid hypertrophy (AH) is a common comorbidity in pediatric allergic rhinitis (AR). The role of the sensitization to aeroallergens in AR children with AH is still unclear. Methods: 5307 children (2-8 years) with nasal complaints were enrolled in our study to identify the prevalence of AR and the incidence of AH complicated by AR. A smaller cohort including 2292 children was recruited for further confirmation. Basic information, serum total and specific immunoglobulin E (tIgE, sIgE) test, physical examination, and fluoroscopy evaluation were obtained for each patient. Risk factors for AH were estimated by logistic regression analysis. Results: We found that 3066 of 5307 children with nasal complaints had an elevated sIgE for at least one aeroallergen. House dust mites (HDMs) were the most common aeroallergen with a prevalence of 65.7%. Of 3066 children with AR, 1440 developed a moderate to severe AH. AR children with AH had a significantly higher tIgE level compared with those without AH (178IU/ml [interquartile range, IQR: 61.2-423.8] vs. 102IU/ml [IQR: 60.0-303.8], p<0.001). Sensitivity to Aspergillus fumigatus (Odds ratio [OR]: 1.687; 95% confidence interval [95%CI]: 1.199-2.373, p=0.003) and cockroaches (OR: 2.295, 95%CI: 1.263-4.170, p=0.006) was statistically significant in the logistic regression model after adjusting for several likely confounders. Conclusions: HDMs are the most common causes among sensitized children with nasal discomforts. AR children with higher tIgE may have higher likelihood of developing AH. AR children with AH have a distinct sensitization profile, and Aspergillus fumigatus and cockroaches could be the main triggers in urban China.