Previous epidemiological studies have associated parental smoking with an increased incidence of lower respiratory illness and bronchial asthma. The aim of the present study was to investigate the association between parental smoking habits and diagnosed wheezy bronchitis in schoolchildren in Saudi Arabia. In a cross-sectional study 3,041 schoolchildren ages seven to 12 years were randomly selected in Dammam, Jeddah, and Riyadh, representing three different geoclimatic regions of Saudi Arabia. Standardized questionnaires were used in our study. The results showed that paternal smoking had a significant effect on the frequency of wheezing when paternal and maternal smoking were considered separately. There was no considerable variation in the parental smoking habits in three areas. The association between passive smoking and diagnosed wheezy bronchitis and frequency of wheezing attacks was highly significant (P<0.0001). Overall, the results tend to confirm that there is a real effect of passive smoking on the respiratory health of children and that parental smoking is a risk factor for wheezy bronchitis in children.