Mayweather, who turns 37 on Monday, revealed the news via Twitter, ending months of speculation about his next opponent.
Mayweather defeated Saul Canelo Alvarez in his most recent bout in September and subsequently announced the May 3 fight without identifying his next opponent. The site for the matchup has yet to be announced.
Mayweather has a perfect 45-0 record while Maidana is coming off an impressive win against Adrien Broner to be 35-3.
Image: Floyd Mayweather Jr.
Photograph: Bryan Haraway/Getty Images
Are Brazilians souring on hosting FIFA World Cup 2014?
Susie Wolff to drive in F1 Friday practice sessions
15 Unforgettable moments from the Sochi Winter Olympics
Sochi Winter Olympics: Take a look at the winning and losing moments!
Mourinho will 'unfriend' Drogba for 90 minutes of Champions League action