The purpose of this paper is to present the prevalence of asthma by occupation and industry in the United States. Self-reported asthma data from the third National Health and Nutrition Examination Survey, 1988-1994 were analyzed. The analysis was restricted to the nonsmoking interview respondents (n= 10,235) aged 17 years and older. The sample data were weighted to reflect national estimates of asthma prevalence by age and race. Information on occupation and industry were coded using the 1990 United States Bureau of Census Occupational code. The software for Survey Data Analysis (SUDAAN) was used to estimate the standard errors of asthma prevalences by occupation and industry. The 95% confidence intervals for asthma prevalences were computed. The overall prevalence of self-reported asthma was 6.6% (95% confidence interval [CI]=5.8-7.4) for males and 6.8% (95% CI=5.9-7.7) for females. Among occupational groups, top five highest prevalences of asthma included 18.7% for protective service occupation, 13.7% for moving vehicle operators, 12.6% for teachers, 11.7% for technicians, and 10.2% for engineers and scientists. Among industrial groups, the highest prevalence was 14.4% for hospital industry workers. In contrast, the lowest prevalence was 0.3% for agriculture services, forestry, and fishing industries. These findings provide useful information for appropriate prevention and control strategies of asthma in the workplaces and for further epidemiologic study to investigate occupational risk factors of asthma in occupations or industries with high asthma prevalence.