The US First Lady will make her third visit to the talkshow programme on Wednesday, August 29 as part of her back-to-school media tour.
She made her Late Show debut earlier this year in March, followed by her second appearance in June when she presented Letterman's 'Top Ten' list.
Obama recently sat down with Jay Leno on his own chatshow for the third time.
Obama previously joked that she wished she was Beyoncé .
"Gosh, if I had some gift, I'd be Beyoncé. I'd be some great singer," she admitted.
Watch Michelle Obama at an Olympics event at the US embassy below: