Thousands of protesters are expected to attend Invasion Day and Survival Day rallies around the nation, with major events held in every capital city.
Demonstrators in Melbourne are expected to descend on state parliament from 10am (AEDT) on Friday in what organisers describe as one of the longest-standing protests in the world.
"Australia Day is not a day to celebrate," Warriors of the Aboriginal Resistance said in a statement on social media.
"It is an annual reminder of invasion, occupation, genocide and the ongoing impacts of colonisation that continues to destroy our lives, our lands and our waters."
Sydney's major demonstration is scheduled at start at Belmore Park at 10am (AEDT) before heading to Victoria Park.
Organisers are calling for an end to deaths in custody, to stop housing and healthcare discrimination, for government to implement all recommendations of the 1978 Royal Commission into Aboriginal Deaths in Custody and a range of other concerns.
Hobart's rally is at Elizabeth Street from 11.15am (AEDT) and the number of people there is expected to surpass those who attended in 2023, according to Tasmanian Aboriginal Centre campaign manager Nala Mansell.
"'January 26th has become the one day of the year that completely divides the nation," Ms Mansell said.
"These protests will keep getting bigger every year, until the prime minister is willing to show some leadership by abolishing the Australia day celebrations, or at least changing the date''.
Brisbane's rally was set for Queens Gardens at 9am (AEST) while in Darwin demonstrators were due to arrive at Civic Park from 8.30am (ACST) .
Adelaide's event starts at 11am (ACDT) in Victoria Square and the Perth march will start at Forrest Chase from 12.30pm (AWST).
Rachel Ward - AAP