Favre was at Levi's Stadium for National TIght End Day and to meet with his friend, and fellow former Southern Miss quarterback, Nick Mullens.
Garoppolo grew up a Bears fan in the Chicago area.
"I gotta say, man, I was a Bears fan growing up, but you were the only Packer that I liked," Garoppolo told Favre.
The NFL posted the following clip of the two quarterbacks interacting, which is meant for the show The Grind on EPIX.
Favre also took time after the game to head into the 49ers locker room and meet with tight end George Kittle.