BACKGROUND: The prevalence of allergy and asthma among children is increasing in many countries. However, such inclination has not been completely cleared in North of Iran. This study was carried out to evaluate the prevalence of asthma and allergic diseases in school children in Gorgan and also to evaluate the association between allergies and sex, family history of atopic disorders, and personal symptomatic atopy. METHODS: This was a cross-sectional study and the study population included 2800 school children aged 12 to 13 (53% female and 47% male). All participants completed an ISAAC (International Study of Asthma and Allergies in Childhood) written questionnaire. RESULTS: Among the selected children, 7% were asthmatic, 19% had eczema during the last 6 months, and 35.3% had rhinitis. Family history of allergy included 8.4% asthma, 22.1% rhinitis and 12% eczema. CONCLUSIONS: The prevalence of asthma is higher in boys compared with girls. There was a strong relation between family history of atopy and allergic diseases and asthma in children.