Abstract: Objective： To investigate the prevalence situation of bronchial asthma among the Li people in Hainan， discuss and analyze the pathogenic factors that influence the prevalence of bronchial asthma among the Li people in Hainan.Methods： Establishing unified questionnaire according to epidemiological investigation method and selecting 100 people for each group randomly among the gathering Li people in the way of stratified multistage cluster and random sampling.Results：The prevalence rate of bronchial asthma was 3.4% in total among the Li people in Hainan. According to the investigation， the prevalence rate of bronchial asthma differed from place to place， males′ prevalence rate was roughly the same as the females′， the teenagers′ was much higher than the young adults′. The prevalence rate among the old had the tendency to increase. The factors that influenced this rate also included the education level， the habits of drinking and smoking， family histroy， environment， unhealthy life styles and physical quality， etc. Conclusion： Smoking and drinking habits， family history and living environment of the Li people in Hainan are the important factors that affect the prevalence of bronchial asthma.