Abstract: Objective To compare the positive rate of allergens between children and adults with atopic diseases and analyze the influencing factors of atopic diseases for making preventive measures.Methods The participants were selected from outpatients in allergy department with simple random sampling.All the participants completed a questionnaire and the test for specific serum IgE antibodies to common allergens.Fisher's exact probability was used to analyze the difference in positive rate of allergens between children and adults.At the same time,we investigated the risk factors of atopic diseases by using univariate and multivariate logistic regression model.Results The differences in positive rate for cow milk,fish and crab were significant between children and adults with atopic diseases.Residential area(odds ratioOR=0.398,95% confidence interval95%CI:0.163-0.974) and the intake of raw or cold food more than three times per week(OR=2.755,95%CI:1.184-6.410)were significant factors in children.Residential area(OR=0.393,95%CI:0.220-0.702),the intake of fried food two or three times per week(OR=2.172,95%CI:1.266-3.726) and more than three times per week(OR=2.217,95%CI:1.038-4.735)were significant factors in the adult females.However,these factors were not significant in adult males.Conclusion When compared with the adult patients,the children with atopic diseases seem to be more sensitive to allergen of cow milk and fish and less sensitive to crab.Living in the urban area is a common risk factor both in children and adult females.Intake of raw or cold food more than three times per week is a risk factor in children and intake of fried food more than two times per week is a risk factor in adult females.