This study examines the role of need for affect (NFA) and perceived prior knowledge about HPV in processing messages about the vaccine. In an experiment with 479 US parents of unvaccinated children, participants were assigned to one of the three conditions (narrative, non-narrative, or no message). Results showed that perceived prior knowledge and NFA were positively correlated with transportation, vaccination intentions, and information-seeking. The effects of NFA were stronger in the narrative condition. For parents with low perceived prior knowledge, NFA was linked to transportation and intentions in the narrative condition, but this was not observed for those with high prior knowledge or in non-narrative conditions. The study discusses its theoretical and practical implications.