Background: Children with asthma, hay fever, and food allergy may have several factors that increase their risk of speech disorder, including allergic inflammation, ADD/ADHD, and sleep disturbance. However, few studies have examined a relationship between asthma, allergic disease, and speech disorder. We sought to determine whether asthma, hay fever, and food allergy are associated with speech disorder in children and whether disease severity, sleep disturbance, or ADD/ADHD modified such associations. Methods: We analyzed cross-sectional data on 337,285 children aged 2-17 years from 19 US population-based studies, including the 1997-2013 National Health Interview Survey and the 2003/4 and 2007/8 National Survey of Children's Health. Results: In multivariate models, controlling for age, demographic factors, healthcare utilization, and history of eczema, lifetime history of asthma (odds ratio [95% confidence interval]: 1.18 [1.04-1.34], p = 0.01), and one-year history of hay fever (1.44 [1.28-1.62], p < 0.0001) and food allergy (1.35 [1.13-1.62], p = 0.001) were associated with increased odds of speech disorder. Children with current (1.37 [1.15-1.59] p = 0.0003) but not past (p = 0.06) asthma had increased risk of speech disorder. In one study that assessed caregiver-reported asthma severity, mild (1.58 [1.20-2.08], p = 0.001) and moderate (2.99 [1.54-3.41], p < 0.0001) asthma were associated with increased odds of speech disorder; however, severe asthma was associated with the highest odds of speech disorder (5.70 [2.36-13.78], p = 0.0001). Conclusion: Childhood asthma, hay fever, and food allergy are associated with increased risk of speech disorder. Future prospective studies are needed to characterize the associations.