Mayweather, considered in some quarters the best pound-for-pound boxer in the world, is believed to have been denied a visa as a result of his history of domestic violence.
Mayweather has been arrested three times in connection with domestic violence, serving 90 days in jail in 2012 for his assault on the mother of his children Josie Harris.
Assistant Immigration Minister Michaelia Cash said: "The Government takes very seriously its role in protecting the Australian community from the risk of harm by non-citizens who engage in criminal conduct and/or conduct that is of serious concern.
"Visa applicants must demonstrate they are of good character, as required under the character test in the Migration Act 1958, before they are granted a visa."
Cash told the Herald Sun: "A visa has not been granted in this case."
US sports website Deadspin did an in depth piece on Mayweather's history of domestic abuse last year, you can read it here.