Mary Lou McDonald has said she would "absolutely" be willing to speak to the family of Paul Quinn.
It comes after the mother of the 21-year-old - who was ambushed, beaten and killed by a gang of men near Oram in Co Monaghan in 2007 - called on the Sinn Féin leader to request an apology from a member of the party over comments made about the case.
The Independent Monitoring Commission said it believed the IRA was involved in the murder and it was the result of a local dispute.
After the killing, Sinn Féin's Conor Murphy said he had spoken to the IRA and was satisfied it wasn't involved.
Paul's mother Breege told the Hard Shoulder yesterday that she wants Mary Lou McDonald to get answers in relation to the claims.
She called on Ms McDonald to ask Mr Murphy to give the family the names of the IRA members that he said he talked to.
Mrs Quinn has also urged the electorate to remember her son when voting.
Speaking on Newstalk Breakfast this morning, Ms McDonald said: "I hope to speak to Conor [Murphy] later.
"This young man, Paul Quinn, got an absolutely horrific death, and just to say the criminals in this scenario are those that give that man such a horrific death.
"Paul Quinn was not a criminal, and so far as I'm concerned Conor has never asserted that Paul was a criminal. I've heard that his parents and his families are upset, and I want to sort that out."
She added: "I think at this stage Conor needs to talk directly to the family, because they're fully entitled.
"They've lost their son in a really brutal way - the last thing they need is the additional sting and pain of any suggestion that the man was a criminal. I am happy to clarify: he was not a criminal. He was brutally beaten to death."
She also stated that she would "absolutely" be willing to speak to the Quinn family herself, adding: "There's no question about that."
Ms McDonald appeared on Newstalk Breakfast this morning after the latest opinion poll showed Sinn Féin as the most popular political party in the country.
The Irish Times/Ipsos MRBI poll has the party holding a two-point lead ahead of its closest rival with 25% of support.
The party is up four points compared to the last comparable poll at the beginning of the campaign in January.
Fianna Fáil is in second place with 23%, down two points, while Fine Gael is in third with 20%, down three points.
With Sinn Féin only running 42 candidates in the general election, Ms McDonald was asked whether she believes she will have to wait until the next election before she has a chance to become Taoiseach.
She responded: "Let's get this election done first - and I just very much hope people will come out and use their vote.
"I'm saying - give us the chance... not because we're entitled to it because it's our turn... give us the chance to demonstrate that government can be different, can be responsive.
"[You can then] judge us on our delivery."