The annual event marks the successful 1967 referendum when Australians voted to count Indigenous Australians as part of the population.
Australian filmmaker Rachel Perkins, of the Arrernte and Kalkadoon Nations, spelt out the importance of a national vote during a speech on Friday.
"We have learned a lesson from history, from our most successful referendum ever, that it takes people from all walks of life, all religions, all ages, genders, professionals, and importantly ... all political persuasions, to move our nation forward," Ms Perkins said during an event in Sydney.
"We ask for a voice in our own affairs, an Indigenous grassroots advisory body guaranteed by the founding document of this modern nation."
A First Nations voice is a practical solution that ensures Indigenous people always have a seat at the table, even if advice isn't always heeded, Ms Perkins said.
She was was joined by major religious groups at the Cutaway at Barangaroo.
Signatories to a Joint Resolution called for bipartisan action to hold a referendum on a First Nations voice, endorsing the proposal as "necessary, right, and reasonable".
The speech coincided with an announcement in Queensland that Lincoln Crowley QC will be the state's first Indigenous Supreme Court judge.
Premier Annastacia Palaszczuk said she understood Mr Crowley's appointment could also be an Australian first.
"It makes our country great, we're all equal, and to see this happen, I can't wipe the smile off my face," Ms Palaszczuk said.
"Hopefully it is the sign of many more to come."
Mr Crowley is the chair of the Bar Association of Queensland's Indigenous Barristers Committee and has previously been a Crown Prosecutor for the Commonwealth Director of Public Prosecutions in Sydney.
He was also a Principal Crown Prosecutor for the Queensland Office of the Director of Public Prosecutions on the Sunshine Coast, and was appointed Queen's Counsel in 2018.
