Taoiseach Enda Kenny said the vote on a constitutional amendment on the protection of children would be held on Nov 10.
The National Youth Council of Ireland said a weekend date would make it easier for young people in education, training, or working away from home to participate.
The wording will be published today and the process of establishing an independent referendum commission will also begin.
The wording is expected to strongly reflect the opinions of a 2010 all-party, Oireachtas committee, and include circumstances where the State can intervene to protect children from abuse.
The 31st amendment to the Constitution Bill is also expected to help remove inequalities in adoption.
The Government will separately brief leaders from Fianna Fáil, Sinn Féin and the Technical Group this morning before announcing details of the referendum.
Some opposition TDs are annoyed they were not consulted on the wording before the Cabinet agreed on it.
The chairperson of the referendum commission is also due to be named today and separately, it will reveal details of its information campaign.
Numerous reports have highlighted failure by the State to protect children. There were calls for amendments to the Constitution in a recent review of the deaths of children in care, and in the aftermath of the Kilkenny incest case and the Roscommon child care case in previous years.
Unesco’s chair of children, NUI Galway’s Professor Pat Dolan, said the vote “could be a defining moment for children and young people in Ireland”.
But a retired judge who was among the first to call for a children’s rights referendum nearly 20 years ago warned yesterday about a long and irrelevant debate.
Mrs Justice Catherine McGuinness said a lengthy campaign would result in fighting over irrelevant points, which would be counter-productive.
With just over seven weeks until polling day, Barnardos chief executive Fergus Finlay predicted a two-month campaign.
“I think a month in the Oireachtas and a month out being debated by the people is more than enough time.”
Meanwhile, it is understood that the Adoption Amendment Bill, which will also be published today, will not deal with the issue of tracing and information rights for the 55,000-plus adopted people in Ireland.
Groups representing adopted people have lobbied for such rights for decades.
Earlier this year, Francis Fitzgerald, the children’s minister, said the issue would be dealt with in a separate Adoption (Information and Tracing) Bill which is being drafted.