The Prime Minister has declared a biosecurity emergency and announced Level 4 travel restrictions for the first time in Australia's history.
Scott Morrison has addressed the nation this morning, telling people not to leave the country under any circumstances.
The PM has also decided to make bans on "non essential" gatherings even tougher.
It means no more than 100 people will be allowed in some indoor areas, like pubs and clubs. However public transport, shopping centres, hospitals and other essential services will be exempt.
There are also restrictions on who and how many people can access aged care homes.
Mr Morrison says schools will remain open and is urging us to continue practicing social distancing.
He's hit out at those hoarding essential supplies, calling it "un-Australian". He says any measures put in place will need to stay for at least six months.