The US musician made a well-received debut hosting the ceremony last year and will take the reins again in January, the Recording Academy said.
In a statement, Keys said: “At first, I did think last year was a one-time thing, but when the opportunity came back around, there was no question about returning as host.
“Last year was such a powerful experience for me. Not only did I feel the love in the room, but I felt it from around the world, and it confirmed the healing and unifying power of music.”
Keys, who has won 15 competitive Grammys, will be the third woman to host the ceremony more than once.
US talkshow host Ellen DeGeneres hosted in 1996 and 1997 while comedian Rose O’Donnell had the honour in 1999 and 2000.
Keys released her debut album, Songs In A Minor, in 2001. She has since become one of the biggest-selling artists ever, with hit singles including Un-thinkable (I’m Ready), No One and Fallin’.
Nominees for the 62nd annual Grammy Awards will be announced on Wednesday, November 20.
The main ceremony will take place on Sunday, January 26, 2020.
Additional reporting by Press Association.