Andy Walton, from the Centre for Theology and Community, is a Christian and part of the choir formed from 64 members from each club.
Aston Villa play Arsenal, and before the match the choir will be singing the hymn 'Abide With Me'.
Andy told Premier: "So I'm a Bolton fan, for my sins so they say, so I was brought up in Bolton, been a Bolton fan much of my life.
"It's a real honour to be representing the club at Wembley, I'm really really excited about it."
He added: "To sing a hymn, and it really is an astonishing hymn, the words of it are about the faithfulness of God.
"I just think it's an amazing thing to be able to do and it's a real tradition, they've sung 'Abide With Me' before the cup final every year before 1927, so it's been part of a famous old tradition."
Listen to Premier's Hannah Tooley speaking to Andy Walton here:
