The presenter tied the knot with Anne-Marie Corbett last weekend, and according to guest David Walliams, he and Dec cracked out a performance of their old hit.
According to The Sun, Walliams spilled the beans during an appearance on The Lateish Show With Mo Gilligan.
He said: “Ant and Dec also did Let's Get Ready To Rhumble on the dancefloor.
“I filmed it and said to Dec, ‘Can I put this on social media?’. He said no and I was really sad. It's one of the funniest things you have ever seen.”
Ant and Dec unveiled Let’s Get Ready To Rhumble in 1994, when they were working as a music double act called PJ & Duncan.
It reached number nine in the charts when it was first released but in 2013 it hit the top spot after the cheeky duo performed it on their show Saturday Night Takeaway.
Ant and Corbett - who was formerly the star’s personal assistant - exchanged vows at a rural church in Hampshire on 7 August.
Celebrity guests included TV stars Dermot O’Leary, Phillip Schofield, Patrick Kielty and Cat Deeley.
Britain’s Got Talent judge Alesha Dixon was also there, along with former footballer Frank Lampard and his television presenter wife Christine.
Watch: Ant McPartlin and Anne-Marie Corbett beam as they begin married life together