Previous research shows that the health behavior of immigrants is favorable to that of native-born adults in the United States. We utilize pooled data from the 1998-2001 National Health Interview Surveys and multinomial logistic regression techniques to build on this literature and examine the association between acculturation and immigrant smoking and alcohol use. We also examine how acculturation relates to health behaviors by gender. Results indicate that the health behavior of more acculturated immigrant women is less positive than that of less acculturated women. For men, acculturation seems to make little difference for health behavior. Thus, it is important to not only consider how acculturation is related to health, but how the acculturation process differs across population subgroups. (Contains 3 tables.)