Barclay Nettlefold has resigned as president of Swimming Australia after making inappropriate and lewd comments.
Nettlefold had already been stood down by the Swimming Australia board after allegations of inappropriate behaviour and comments were levelled at the president following two separate incidents in Adelaide in April.
He had been in the post since October.
Nettlefold said in a statement: "My decision to step down will ensure the significant progress and substantial positive change to the sport of swimming in this country continues.
"There were some private comments I made in jest to my colleagues recently that were not consistent with the standards expected of me, standards I have urged to be incorporated into the future culture of Swimming Australia.
"I am proud to have initiated two independent inquiries into swimming and I commend the people who have worked with me and supported the drive for change. They all have the institution of swimming in Australia at their heart and together I believe we have made great progress in a very short period of time."
Swimming Australia said a new president could be named in the next few days.
Nettlefold had overseen a major overhaul of Swimming Australia in the wake of a troubled Olympic Games in London last year in which Australian swimmers underperformed in the pool and were accused of misbehaviour out of it.
In April, Mark Anderson, the former head of Hockey Australia, the national field hockey body, took the chief executive’s post, replacing Kevin Neill, while Michael Scott, a former performance director at British Swimming, replaced Leigh Nugent in the same role at Swimming Australia.
Australia's swimmers won just one gold medal, plus six silver medals and three bronze medals in London, the team’s lowest total since the 1992 Olympics in Barcelona.
The team failed to win an individual gold medal for the first time since the 1976 Montreal games.