From Monday, all Aboriginal and Torres Strait Islander Victorians over the age of 16 will be able to vote to elect representatives for the First Peoples' Assembly.

"When the state government said they were ready to sit down as a sovereign entity to negotiate a treaty or treaties, I thought, oh my god now what do we do? Who do they talk to?" Treaty Advancement Commissioner Jill Gallagher told AAP.

"The First People's Assembly will be that counterpart to government. They will be the community voice in the next stage of treaty and they will have a mandate to do that because the mob would have elected them."

The elections come after three years of community consultation led by Ms Gallagher, who said the process had to be developed from scratch.

The assembly will be made up of 33 representatives from five geographical voting areas, four in regional Victoria and one in metropolitan Melbourne.

About 30,000 people are eligible to vote, and the ballot will be open for five weeks to elect 21 assembly members.

The remaining 12 seats have already been allocated to formally-recognised traditional owner groups.

Despite low Aboriginal voter turnout at recent federal and state elections, Ms Gallagher is hopeful of high participation.

"There's excitement in the air. Across the state, our own people are enrolling to vote and some are learning to campaign. It's pretty powerful," she said.

Votes can be cast in person, online and by post and people can enrol on the day.

The election process isn't without controversy, with some people saying they won't vote unless the government scraps plans to bulldoze hundreds of sacred trees in the state's west to make way for a highway.

About 500 protesters gathered at parliament this week chanting "no trees, no treaty", including former Greens MP Lidia Thorpe, who is listed as a candidate for the First People's Assembly in the Metropolitan division.

Ms Gallagher said she hoped the treaty momentum wasn't derailed by the protest movement.

"Aboriginal people in Victoria, in Australia, have waited 240 years to have recognition that we are the first people's of this country and that we didn't cede our sovereignty," she said.

"I am damn sure I am going to stay focused on that goal."

* Voting for the First People's Assembly is open from Monday September 16 to Sunday October 20

For further information visit www.firstpeoplesvic.org

Australian Associated Press