The functions of Project Portfolio Management Offices (PfMOs) support not only implementation of organizational strategic management and investment decisions but also ensure that organizational benefits are realized and successfully delivered by projects and programs. Nevertheless, the association between PfMO functions and project success remain under-researched. The aims of this research are to address PfMO functions commonly performed and review magnitude of the functions from Australian perspectives. Furthermore, the research significantly focuses on the association between PfMO functions and project success. The research data collection was conducted using questionnaire survey with 27 senior project and portfolio management professionals working in 6 Australian sectors. The relationships of 52 PfMO functions were cross-examined against 8 project success criteria using a statistical correlation analysis. The significance of PfMO functions in project success is highlighted. The correlation findings reveal diverse combinations of relationships between PfMO functions and project success in differing Australian sectors. Further discussion is provided for specific sectors to achieve higher performance of PfMO functions.