The former First Lad shared an Instagram post to her 33.2 million followers praising the royal, who is currently mid-way through a tour of South Africa together with husband Prince Harry and son Archie.
The post includes a picture of the Duchess of Sussex, 38, posing with leaders at the Obama Foundation – a charity founded by Michelle’s husband Barack – during an engagement yesterday.
In the post’s caption, Obama, 55, thanked her “friend” the Duchess for “breaking the mold and making our world better for it”.
Obama isn’t the only high-profile figure to praise the Duchess’ work.
In Victoria Beckham’s recent interview for Glamour magazine, the 45-year-old said of Meghan: “Women supporting women is key. I liked what Meghan Markle said at the [British] Fashion Awards, that it used to be cool to be cruel, and now it's cool to be kind.
“Kindness was always at the core of Girl Power."
How does Meghan Markle know Michelle Obama?
Duchess Meghan interviewed Obama for an interview when the latter guest-edited the September issue of British Vogue.
In the introduction, the royal described the former FLOTUS as “kind, inspirational, motivating, funny”, while the pair discussed motherhood and changing life goals in the piece.
READ MORE: Michelle Obama's advice to Meghan Markle
It is believed they knew each other before this time.
Michelle and Meghan are believed to have first met when the former First Lady was in London to promote her book ‘Becoming’ last December.
Prior to this, the Duchess met then US-President Barack Obama back in 2015 and posted a photo with him on her now-deleted Instagram page at the time, with the caption: "Such a pleasure to meet you Mr. President @barackobama #grateful.”