Asthma is a health problem throughout the world. The previousclassification of asthma by severity is now recommended only for researchpurposes. Instead, a classification of asthma by level of control isrecommended. The present study aimed at estimating the prevalence ofasthma among school age children in Cairo, Egypt and its level of control.Also, we tried to study the risk factors associated with asthma & factorsthat might affect the level of control. Written questionnaire was applied on2394 school age (5-18years -randomly selected) children from Nasr city-Cairo Governorate. The study revealed the following: The prevalence ofpediatric asthma in Cairo was 10.44%, and 43.6% of asthmatics were firstchildren in their families. Family history of allergy and presence ofhousehold animals were significantly higher in families with asthmaticchildren. Uncontrolled asthma was detected in 19.2% of children, while40.4% were partly controlled and 40.4% were well controlled. Maternaleducation and receiving medical information about asthma were significantfactors associated with asthma control. The study concluded that asthma isa prevalent disease in children living in Cairo that requires collaborativemeasures for better control of this disease.