BACKGROUND Pregnant women are the highest priority group for seasonal influenza vaccination. However, their vaccination uptake remains suboptimal. The purpose of this study is to explore Hong Kong women's perceptions of the threat of influenza infection during pregnancy, the risks and benefits of influenza vaccination, and their decision-making processes. METHODS We used a qualitative descriptive design and recruited women who had just given births to a live infant from April to June 2011. Participants were recruited from a large teaching hospital in Hong Kong and were interviewed in the immediate postpartum period. RESULTS A total of 32 postpartum women were interviewed, and two had been vaccinated during pregnancy. Following thematic analysis, three themes emerged: perceived risk of influenza infection, perceived risk of influenza vaccine, and decision-making cues. Overall, participants held negative impressions about influenza vaccination during pregnancy, and they underestimated the threat of influenza to themselves and their fetus. They were also confused about the safety and efficacy of the influenza vaccine and the differences between preventive strategies and treatment for influenza. Most participants reported that their health care providers (HCPs) did not offer or recommend vaccination. Because of negative media reports about vaccination, participants were hesitant to receive the vaccine. Motivating forces for vaccine acceptance were a perceived high prevalence of circulating influenza during their pregnancy and HCP recommendations and reassurances that the vaccination was safe, effective, and beneficial for the fetus. CONCLUSIONS Vaccination promotion strategies need to focus on encouraging HCPs to take the initiative to discuss vaccination with their pregnant clients and provide accurate and unbiased information about the risks of influenza and the benefits of vaccination.