U.S. universities are increasingly racially/ethnically diverse. Simultaneously, undergraduate graduation rates and alcohol use remain important concerns. Understanding factors that contribute to success and well-being among students in these diverse college settings is critical to informing educational policy and programming. Polyculturalism is the belief that different racial/ethnic groups have always interacted, exchanged, and influenced each other, and it has been associated with more positive intergroup attitudes and greater comfort with diversity. Across four studies (three cross-sectional, one longitudinal) with racially/ethnically diverse undergraduates at two diverse institutions in the Northeastern United States, controlling for potentially confounding variables (year in college, age, race/ethnicity, nativity, high school GPA, current GPA, endorsement of multiculturalism and colorblindness, self-esteem, ethnic identification, general social anxiety, and mood across time points), greater endorsement of polyculturalism was associated with greater academic self-efficacy, greater sense of belonging, less use of alcohol to cope with intergroup anxiety, and fewer adverse alcohol-related consequences;