OBJECTIVE: To study the prognosis of childhood asthma and the factors influencing asthmatic attacks and prognosis. METHODS: The medical data of 212 children with asthma who were followed up for more than 5 years were retrospectively studied. RESULTS: During the 5-year follow up, asthmatic attacks termination was found in 121 cases (57.1%) and asthma persistence was observed in 91 cases. Respiratory tract infections were found as the major factors inducing asthmatic attacks (71.7%), followed by inhaled allergens (17.0%).The children with asthma induced by respiratory tract infections had a higher remission rate of asthmatic attacks (61.2%) than those induced by allergens (41.7%) or exercises (26.3%). Three risk factors for asthma persistence were identified: concurrent allergic rhinitis and eczema, parental asthma and allergy-induced wheezing. CONCLUSIONS: The 5-year follow-up study demonstrated that asthmatic attacks stopped in the majority of children with asthma. Respiratory tract infections may be the major factors inducing acute asthma attacks. The children with asthma induced by respiratory infections may experience a better outcome. Atopic children or children with the genetic background of atopy are at high risks for the development of persistent asthma.