tToxocara canis, Toxocara cati, are roundworms that live in the intestines of dogs and cats, respectively,and are predominantly agents of human toxocariasis. Studies have suggested that Toxocara spp. sero-prevalence increases levels of total and aeroallergen-specific IgE (sIgE), asthma prevalence and asthmamorbidity. Nevertheless, other work reported a negative association between Toxocara spp. seropositivitywith skin hypersensititity and a positive association with sIgE. The objective of the present study was toevaluate risk factors for acquiring Toxocara spp. infection and to investigate possible significant associa-tion between its seroprevalence with atopy and asthma. Students from elementary schools, residents in asmall town and its surroundings of Northeast Brazil, underwent blood sampling to measure levels of anti-Toxocara spp. IgG, peripheral blood eosinophils, and specific IgE to aeroallergens. We used univariable andmultivariable logistic regression analyses to assess possible risk factors for Toxocara spp. seropositivityand its association with atopy, wheeze/asthma with asthma phenotypes, in a sample of 791 elementaryschool children aged 6–13 years. Toxocara spp. seroprevalence reached 63.6%; 49.9% had sIgE; 7.2% and3.3% had atopic wheeze/asthma and non-atopic wheeze/asthma respectively. Risk factors associated withToxocara spp. seropositivity were: contact with dogs (adj. OR 2.33; 95% CI = 1.70–3.19) and cats (adj. OR3.09; 95% CI = 2.10–4.55), and male sex (adj. OR 2.21; 95% CI = 1.62–3.02). The presence of anti-ToxocaraIgG was statistically associated with blood eosinophils >4% and >10% (adj. OR 1.84; 95% CI = 1.33-2.55 andadj. OR 2.07; 95% CI = 1.45–2.97, respectively), and atopy (adj. OR 2.00; 95% CI = 1.49–2.68), but it was notassociated with wheeze/asthma. Concluding, the results obtained in this study showing the association ofToxocara spp. seroprevalence with sIgE may suggest a possible immunological cross-reactivity betweenIgE epitopes from Toxocara spp. and aeroallergens