The pair will be hitting the road together for the All The Hits Tour, headlined by Lionel with Mariah as a special guest. The 35-date tour kicks off in Baltimore on 15 March (17) and wraps in Fort Lauderdale on 27 May (17), with tickets going on sale on Saturday (10Dec16).
Both Lionel and Mariah are hugely successful in their own rights, with the 67-year-old enjoying a rise in popularity among the younger generation in recent years, and Mariah documenting her recent Sweet Sweet Fantasy European tour in new E! reality series Mariah's World.
While the set list for the tour has yet to be announced, it has already been speculated that Mariah and Lionel will team up for hit duet Endless Love. Lionel initially had a hit by teaming up with Diana Ross on the romantic ballad, while Mariah's cover with Luther Vandross was also hugely successful.
Mariah and Lionel previously shared the same stage as they were both among performers at a public memorial for late singer Michael Jackson in 2009.
Taking to Twitter to respond to critics of her performance at the event, Mariah said at the time: "Trying to sing today was basically impossible for me. I could barely keep myself from crying. I'm sorry that I wasn't able to pull it together and really do it right, but I was literally choked up when I saw him there in front of me."
"One thing I know is, we will never really have to say goodbye to MJ. His legacy lives on through his music and the millions of people. He inspired with his timeless music. He will be forever in our hearts."