Background: Health effects due to air pollution is becoming a major public health problem with growing traffic congestion and establishment of small- to medium-scale industries with poor emission controls in urban cities of Sri Lanka. Methods: Respiratory health status of 7- to 10-year-old children in two settings (urban and semi-urban) was assessed using standard questionnaires. Information on socio-demographic characteristics and potential determinants of both outdoor and indoor air pollutants exposure levels were also obtained. The respiratory health status of children in the two settings was compared. Results: We found that children from the urban setting had a significantly higher prevalence of wheezing within the last 12 months as compared to children from the semi-urban setting (adjusted OR=2.02; 95% CI=1.13-3.59). Indoor cooking with unclean fuels was a risk factor for wheezing independent of the area of residence (adjusted OR=1.57; 95% CI=1.01-2.46). Conclusions: Poor indoor air quality was a major determinant of wheezing for the overall study group. Children from urban areas of Sri Lanka have poorer respiratory health status as compared to children from semi-urban areas. Besides poor outdoor air quality, this difference may also be due to other unexplored factors which may differ between urban and semi-urban areas in Sri Lanka. © 2012 Wiley Periodicals, Inc.