Thousands of protesters are expected to break COVID-19 rules in Melbourne to show solidarity with the Black Lives Matter movement.
Saturday's CBD protest will also call for an end to Aboriginal deaths in custody.
As rallies continue across the United States, the Aboriginal community have organised a protest outside Victoria's Parliament House on Saturday afternoon.
The US protesters have taken issue with police violence against black Americans, sparked by the May 25 death of George Floyd, an unarmed black man who died in police hands in Minneapolis.
More than 14,000 people have said online they will attend Melbourne's event.
More than 400 indigenous Australians have died in police detention since a 1991 royal commission into the deaths of Aboriginal people in custody, according to Amnesty International Australia.
Protest organisers have urged people to wear face masks and bring hand sanitiser as cornavirus measures.
Premier Daniel Andrews has confirmed police don't believe it is feasible to arrest or fine people for breaking coronavirus rules at the event.
Victoria Police Assistant Commissioner Luke Cornelius said he would rather the protest didn't occur at this time, when the spread of COVID-19 remains a threat.
But he stressed the force supports people's right to protest.
He urged Victorians to follow the Chief Health Officer's directions on social distancing to prevent the event becoming a coronavirus "tipping point".
Mr Cornelius said the force was committed to working with the Victorian Aboriginal community.
"I understand from my engagement with local Aboriginal community members that there is a sense of frustration that it takes a death of a black American to highlight the experience of the Aboriginal community here in Australia," he said.
"The events in America certainly do give us an opportunity to reflect on our own community."
Police are also on high alert for counter-protests being held in the city, and the potential for protesters to turn on officers.
The premier said if the protest was not peaceful, police would step in restore order.
"Victoria Police will not tolerate violence and will not tolerate some of the disorder that we've seen overseas," Mr Andrews told reporters.
Shadow attorney-general Edward O'Donohue said aside from the health risks, it was hypocritical for the government to fine people for having a drink without a meal at pubs, but not for gathering in such a large group.
"The prospect of thousands and thousands of people turning up in a confined space, puts at risk everything Victorians have worked collectively to achieve, to manage, throughout the COVID process," Mr O'Donohue said.
Australian Associated Press