To examine health providers' perceived barriers, supports, and vaccination actions in delivering the HPV vaccine to females ages 9-17 in four states. Differences in providers' HPV vaccination of pre-adolescents compared with older adolescents were explored. A random sample of 1,500 pediatricians, family physicians, gynecologists, nurse practitioners, and physician assistants from four states were asked to complete a mail survey. Providers were recruited through state medical and nursing boards. The final sample included 227 respondents. Among those participants, health providers vaccinated older females (ages 13-17) at significantly higher rates than pre-adolescents (ages 9-12) in all four states. Providers who reported increased barriers to HPV vaccination were significantly less likely to vaccinate girls in either age group. The most frequent barriers reported by providers included the financial burden of the HPV vaccine and encountering patients (more often patients' parents) who have negative perceptions of vaccine. Most common supports included a personal belief in the positive impact of the HPV vaccine, followed by providers feeling comfortable talking with parents about the sexual nature of the vaccine, and the importance of adhering to the CDC's recommendations on HPV vaccination. Age of patient will likely influence providers' HPV vaccination behaviors, particularly if parents have concerns about vaccinating their pre-adolescents. Providers can best serve their patients when they are aware of the potential barriers and supports that may influence their HPV vaccination behaviors.