The following lists events that happened during 1905 in Australia.

George Reid

Alfred Deakin

• Monarch – Edward VII
• Governor-General – Hallam Tennyson, 2nd Baron Tennyson (until 21 January), then Henry Northcote, 1st Baron Northcote
• Prime Minister – George Reid (until 5 July), then Alfred Deakin
• Chief Justice – Samuel Griffith

• Premier of New South Wales – Joseph Carruthers
• Premier of South Australia – John Jenkins (until 1 March), then Richard Butler (until 26 July), then Thomas Price
• Premier of Queensland – Arthur Morgan
• Premier of Tasmania – John Evans
• Premier of Western Australia – Henry Daglish (until 25 August), then Cornthwaite Rason
• Premier of Victoria – Thomas Bent

• Governor of New South Wales – Admiral Sir Harry Rawson
• Governor of South Australia – Sir George Ruvthen Le Hunt
• Governor of Queensland – Frederic Thesiger, 3rd Baron Chelmsford (from 30 November)
• Governor of Tasmania – Sir Gerald Strickland
• Governor of Western Australia – Admiral Sir Frederick Bedford
• Governor of Victoria – Major General Sir Reginald Talbot

• 1 March – John Jenkins resigns as Premier of South Australia to become Agent-General for South Australia in London. He is replaced by Richard Butler.
• 12 May – The first meeting of the Australian Council of Defence takes place between the Minister for Defence, the Treasurer, the Inspector-General Army, the Chief of Intelligence, and the Director of the Naval Forces.
• 18 May – A state election takes place in Queensland, returning the government of Arthur Morgan. Women are able to vote in Queensland state elections for the first time.
• 24 May – Empire Day is first celebrated in Australia.
• 28 May – The town of Maryborough in Queensland experiences an outbreak of pneumonic plague.
• 5 July – Alfred Deakin resumes office as Prime Minister of Australia after George Reid is unable to form a stable ministry.
• 26 July – A state election is held in South Australia. The Labor Party led by Thomas Price forms a minority government.
• 6 September – Last sighting of the clipper ship Loch Vennachar which sinks off Kangaroo Island, killing 32 people. Only one body was found.
• unknown dates
  • Non-aboriginal women are given the vote and admitted to the practice of law in Queensland.
  • Workers' compensation is introduced in Queensland.

• Albert J. Hanson wins the Wynne Prize with The Blue Noon

• 1 February – New South Wales wins the Sheffield Shield
• 15 July – Australia first competes in the Davis Cup, in a combined Australasian team with New Zealand.
• 30 September – Fitzroy wins the VFL premiership.
• 7 November – Blue Spec wins the Melbourne Cup.^[1]
• Australia loses cricket series to England 0-2

• 10 January - Albert Arlen, pianist, composer, actor, and playwright (died 1993)
• 15 February – Heathcote Howard Hammer, brigadier (died 1961)
• 1 April – Paul Hasluck (died 1993), Governor General of Australia
• 1 August – Eddie Gilbert (died 1978), cricketer

• 15 January – George Thorn (born 1838), Premier of Queensland
• 6 May – Robert Herbert (born 1831), Premier of Queensland
• 25 June – Augustus Gregory (born 1819), explorer
• 5 July – Henry Baylis (born 1826), police magistrate
• 30 October – Boyd Dunlop Morehead (born 1843), Premier of Queensland
• 29 December – Victor Daley (born 1858), poet

• 1900s (decade)