ABSTRACT: INTRODUCTION:Cervical cancer imposes a substantial health burden worldwide including in Australia and is caused by persistent infection with one of 13 sexually transmitted high-risk human papillomavirus (HPV) types. The objective of this study was to assess the cost-effectiveness of adding a nonavalent new Gardasil-9® (9vHPV) vaccine to the national immunisation schedule in Australia across three different delivery strategies. MATERIALS AND METHODS:The Papillomavirus Rapid Interface for Modelling and Economics (PRIME) model was used to examine the cost-effectiveness of 9vHPV vaccine introduction to prevent HPV infection. Academic literature and anecdotal evidence were included on the demographic variables, cervical cancer incidence and mortality, treatment costs, and vaccine delivery costs. The incremental cost-effectiveness ratios (ICERs) were measured per disability-adjusted life years (DALYs) averted, using the heuristic cost-effectiveness threshold defined by the World Health Organisation (WHO). Analyses and data from international agencies were used in scenario analysis from the health system and societal perspectives. RESULTS:The 9vHPV vaccination was estimated to prevent 113 new cases of cervical cancer (discounted) during a 20-year period. From the health system and societal perspectives, the 9vHPV vaccination was very cost-effective in comparison with the status quo, with an ICER of A$47,008 and A$44,678 per DALY averted, respectively, using the heuristic cost-effectiveness threshold level. Considering delivery strategies, the ICERs per DALY averted were A$47,605, A$46,682, and A$46,738 for school, health facilities, and outreach-based vaccination programs from the health system perspective, wherein, from the societal perspective, the ICERs per DALY averted were A$46,378, A$43,729, A$43,930, respectively. All estimates of ICERs fell below the threshold level (A$73,267). CONCLUSIONS:This cost-effectiveness evaluation suggests that the routine two-dose 9vHPV vaccination strategy of preadolescent girls against HPV is very cost-effective in Australia from both the health system and societal perspectives. If equally priced, the 9vHPV option is the most economically viable vaccine. Overall, this analysis seeks to contribute to an evidence-based recommendation about the new 9vHPV vaccination in the national immunisation program in Australia.