← 1820 1819 1818 1821 in Australia → 1822 1823 1824
Decades:	1800s 1810s 1820s 1830s 1840s
See also:	Other events of 1821 Timeline of Australian history

The following lists events that happened during 1821 in Australia.

• Monarch - George IV

Governors of the Australian colonies:

• Governor of New South Wales- Major-General Lachlan Macquarie until 1 December 1821, succeeded by Thomas Brisbane.
• Lieutenant-Governor of Tasmania - Colonel William Sorell

• 3 February – Sir Thomas Brisbane is commissioned as Governor to succeed Macquarie. He replaces Macquarie on 1 December of the same year.
• February – John Bigge finishes gathering evidence on all aspects of the colonial government, including finances, the church, the judiciary, and the convict system. He then sails back to England.
• 1 May – The Australian Magazine, Australia's first periodical, begins publication.
• 27 June – The Philosophical Society of Australasia is established. It would be renamed as the Royal Society of New South Wales in 1866 at the request of Queen Victoria.
• 29 October – Governor Macquarie lays foundation stone for first Catholic church in Australia, St Mary's.^[1]
• The Female Factory, for women convicts, is separated from the Parramatta Gaol. Many women are selected as brides or for domestic service.^[2]
• Parramatta Marist High School, Australia's first private school, founded by John Joseph Therry.^[2]
• Wool export in Australia - 75,400 pounds.

• March – Port Macquarie, a penal settlement, was established for convicts that had committed secondary crimes in New South Wales.^[2]