The Born This Way singer is to appear alongside the rock and roll legends at The Prudential Centre in Newark, New Jersey on Saturday December 15, the final concert marking the band's 50th anniversary.
Drummer Charlie Watts said: "I think Mick (Jagger) said she wanted to do it without any of that (glitz and glam), which would be fun actually."
"But I don't mind if she dresses up in whatever. He does, so why shouldn't she?" he laughed. "I'll tell you, some of (Mick's) outfits are Lady Gaga."
Despite all the commotion that surrounds Gaga, the Stones believe she's the real deal.
"I think underneath she's very talented," Ronnie Wood said. "I happen to like the way she sings, and it'll be interesting to see the way she handles it."
"I think they've all done interesting things and they're from different kinds of music and they're all American, but they're all different generations so... they represent different parts of American music in a way," Mick said.
The rocker also said he is going to "see what happens" when asked if the band would perform more concerts in the future. "I'm going to see what happens. I've quite enjoyed doing these shows, you know, there's no real reason why you shouldn't do more. But we haven't actually booked any or planned any," he said.
Charlie added: "It's time out your life, doing tours. But as Keith (Richards) would say if he was sitting here, 'What else are you going to do?' And I don't have an answer."