We examined ethnic differences in smoking and drinking habits among the five major ethnic groups in Hawaii (Caucasians, Japanese, Chinese, Filipinos, and Hawaiians) by means of questionnnaire data obtained from a representative sample of 8,636 Hawaii residents. For men, lifetime cigarette use was greatest among Caucasians and lowest among Chinese and Filipinos. For women, smoking cigarettes was highest among Caucasians and lowest among Chinese. Although overall smoking patterns showed some relationship to lung cancer incidence, the observed rates could not be fully explained. Beer consumption was greatest among Hawaiians of both sexes and least among the Chinese; most consumers of spirits (hard liquor) were Caucasian. Total alcohol consumption was similar among Hawaiians and Caucasians and was considerably greater than among the other 3 ethnic groups. Alcohol consumption patterns among men did not correlate well with esophageal cancer incidence, even when the analyses were restricted to smokers; among women, however, the correlation was high. For these sex- and ethnic-specific groups whose alcohol consumption was generally low, there was a negative association of amount consumed with mean annual family income. For the groups with higher proportions of drinkers, mean annual family income was higher among those who drank moderately (less than 5 ounces/wk) than among those who either drank more heavily or not at all.