Ann will discuss the final stretch of the November presidential election with Leno on Tuesday, September 25.
NBC's announcement of Ann's Tonight Show appearance was made days after leaked footage from a private fundraiser showed her husband Mitt Romney weighing in on the late-night battle between Jay Leno and David Letterman.
"I've been on Letterman a couple of times, I've been on Leno more than a couple of times," Romney said in the leaked clip. "Now, Letterman hates me because I've been on Leno more than him. They're very jealous of one another, as you know."
Letterman has since insisted that he does not hate Mitt and invited the candidate to appear on The Late Show in the future.
"I think now, more than ever, he and his lovely wife Mrs. Mitt are more than welcome to come on the show," Letterman told his audience. "And I'm telling you, if you think you're going to get to the White House, you've gotta spend time in this chair."
Mitt has made many talkshow appearances in the last several years, appearing on Leno's Tonight Show four times in the past.
The Tonight Show with Jay Leno airs weeknights at 11.35/10.35c on NBC.
Watch a clip from Mitt Romney's last Tonight Show appearance below: