BACKGROUND AND OBJECTIVES: The development of a vaccine to prevent human immunodeficiency virus (HIV) infection is a highly desirable goal. However, there may be a number of psychosocial barriers to HIV vaccine acceptance. The purpose of this study was to begin to examine some factors that might influence attitudes about HIV immunization. GOAL: To evaluate the relationship of health beliefs and vaccine characteristics to acceptability of hypothetical HIV immunization. STUDY DESIGN: The subjects were 222 college students who completed self-administered questionnaires that addressed health beliefs, vaccine characteristics, and acceptability of hypothetical HIV vaccines. RESULTS: Health beliefs independently predictive of HIV vaccine acceptability included perceived susceptibility to HIV, perceived nonmembership in a traditionally defined acquired immune deficiency syndrome (AIDS) risk group, and fear of the vaccine causing AIDS. Of the vaccine characteristics, efficacy influenced vaccine acceptability most strongly, followed by type of vaccine. CONCLUSION: These results suggest that universal HIV vaccine acceptance cannot be assumed and that vaccine characteristics and individuals' health beliefs are likely to influence decisions regarding HIV immunization.