Allergic diseases are frequent in children and their prevalence and severity differ in the different regions of the world. The association between pet ownership in childhood and subsequent asthma and sensitization is very controversial.In our survey conducted with standardized method (International Study of Asthma and Allergies in Childhood), 3200 children 6-7 years old were questioned regarding asthma, allergic rhinitis and eczema. The prevalence of Attacks and shortness of breath with wheezing during last 12 months in the children who had exposure to pets in the first year of life was 34.3% 'that was less than children who had not exposure (OR=3.06, 95% confidence interval [CI] 1.14-8.21, P=0.021). Also during the past 12 months the prevalence of night dry coughs, allergic rhinitis symptoms and eczema symptoms in those who had pet exposure in the first year of their life was lower than the children did not have it. However there was no significant difference in some other symptoms of asthma in two groups.Our findings suggest that pet exposure in the first year of life can have a protective effect on asthma, allergic rhinitis and eczema.