The US First Lady's appearance with Letterman this evening is the latest in a series of promotional appearances for her new book American Grown: The Story of the White House Kitchen Garden and Gardens Across America.
Letterman previously hosted an appearance by Obama in March.
The popular 'Top Ten List' has drawn a variety of celebrity guests over the years, including Jack Black, Justin Bieber, Lindsay Lohan, and even Homer Simpson.
How I Met Your Mother's Neil Patrick Harris, Noomi Rapace of Prometheus and music guest Alan Jackson will also appear on tonight's show.
The Late Show with David Letterman airs weeknights at 11.35/10.35c on CBS.
Watch Betty White read the 'Top Ten List' below: