The interview on Tuesday with Donald Trump Jr comes as the bipartisan House committee moves closer to the former president's inner circle of family members and political advisers.
The younger Trump is of likely interest to the committee because of his proximity to his father on the day of the riot.
Donald Trump Jr was backstage at the rally on the White House Ellipse that took place shortly before supporters of the then-president marched to the Capitol and breached the building.
In several social media videos posted at the time of the January 6 attack, Trump Jr. was seen with Kimberly Guilfoyle - then his girlfriend, now his fiancee - and other members of his family as his father prepared to make a speech investigators believe rallied supporters to act violently that day.
The House committee has also released text messages from January 6 in which Trump Jr pleaded with the White House to get his father to forcefully condemn the riot.
"We need an Oval address. He has to lead now. It has gone too far and gotten out of hand," Trump Jr wrote to then-White House chief of staff Mark Meadows.
Trump Jr is one of nearly 1000 witnesses the committee has interviewed as it works to compile a record of the worst attack on the Capitol in more than two centuries.
He is the second of Trump's children known to have spoken to the committee - his sister Ivanka Trump sat down with lawmakers for eight hours in early April.
Her husband, Jared Kushner, has also been interviewed by the committee.
Other allies of the former president have defied subpoenas from the committee and been referred to the Justice Department for potential prosecution on contempt of Congress charges.
One of them, Stephen Bannon, was indicted last year after he refused to co-operate. That case is pending.
The committee of seven Democrats and two Republicans is looking to wrap up its nearly 11-month investigation and shift into the public hearing phase.
Hearings are set to begin on June 9 and go on for four weeks.
Politicians expect to bring out witnesses and present evidence in an effort to educate the public on the full scope of the attack and Donald Trump's role in it.
Trump Jr is no stranger to congressional investigations, having testified at least three times in House and Senate investigations of Russian interference in the 2016 presidential election.
The two people who confirmed Trump Jr's interview with the January 6 committee were granted anonymity to discuss the private session, which was not announced by the committee.
