1965 NSWRFL season: St George wins the tenth of a record eleven consecutive premierships in the NSWRL. They were not to win again until 1977, then in 1979 which was their last premiership before their 1999 merger with the Illawarra Steelers.
1 March – The Amateur Swimming Union of Australia stuns the nation with its decision that Olympic champion and 1964 Australian of the Year Dawn Fraser will be banned from all amateur competition for ten years. The decision follows an inquiry into Fraser's alleged misbehaviour during the 1964 Summer Olympics in Tokyo.
August 15 – US swimmer Kenis Moore breaks the world record in the women's 200m butterfly (long course) during a meet in Maumee, Ohio, clocking 2:26.3.
August 21 – Dutch swimming star Ada Kok breaks the world record in the women's 200m butterfly (long course) for the first time, during a meet in Leiden, clocking 2:25.8.
September 12 – Ada Kok from the Netherlands betters her own world record in the women's 200m butterfly (long course), during a meet in Groningen, clocking 2:25.3.