Objective To find out the risk factors of childhood asthma in Yichang city and provide guidance for prevention of the occurrence and exacerbations of childhood asthma. Methods A total of 10 456 cases of children were randomly selected to grant screen questionnaires using cluster sampling method, then screening out the suspected asthmatic ones, granting to them with asthma questionnaire for further investigation, at the same time, the similar number of gender, age-matched non-asthmatic children were selected for the case-control study. Results Personal history of drug allergy, allergic rhinitis, eczema and a family history of asthma or allergies;house walls coating with paint, the use of coal for heating and cooking, the mildew phenomenon, house decoration history, smoking, and using blankets made bedding; adding complementary before 3 months, using antibiotic within 1 year were risk factors of childhood asthma in Yichang city. Conclusion For children who have personal or family history of allergic diseases, parents should try to avoid the allergen exposure in house environment, and actively avoid risk factors can prevent the occurrence of asthma or reduce the incidence of asthma exacerbations times.