Objective: The purpose of this study was to develop a comprehensive health literacy assessment tool for young adult college students. Participants: Participants were 144 undergraduate students. Methods: Two hundred and twenty-nine questions were developed, which were based on concepts identified by the US Department of Health and Human Services, the World Health Organization, and health communication scholars. Four health education experts reviewed this pool of items and helped select 87 questions for testing. Students completed an online assessment consisting of these 87 questions in June and October of 2012. Item response theory and goodness-of-fit values were used to help eliminate nonperforming questions. Results: Fifty-one questions were selected based on good item response theory discrimination parameter values. Conclusions: The instrument has 51 questions that look promising for measuring health literacy in college students, but needs additional testing with a larger student population to see how these questions continue to perform.