Vice Admiral Stuart Campbell Mayer, AO, CSC & Bar (born c. 1965) is a retired senior officer of the Royal Australian Navy. He joined the navy via the Royal Australian Naval College at HMAS Creswell in 1984 and qualified as a Principal Warfare Officer in 1994. He commanded HMAS Canberra (2002–04), HMAS Anzac (2007–09) and the International Stabilisation Force (2009–10), and deployed on operations to the Persian Gulf, East Timor, and the Arabian Sea during the Iraq War. He served as Commander Australian Fleet from 2014 to 2018, Head Force Design within the Vice Chief of Defence Force Group from 2018 to 2019, and Deputy Commander United Nations Command, based in South Korea, from 2019 to 2021. He retired from the navy in 2022 and was appointed a partner in Ernst & Young's consulting division.