The singer, who has had 19 primary singles and bought greater than 200 million albums, will play Pride within the Park on Saturday 1 August.
The three-day occasion runs from 31 July to 2 August. On Sunday, The Pussycat Dolls – who not too long ago reformed – are the headline act.
Chris Jepson, from the pageant, stated Mariah was “a huge LGBTQ+ ally”.
Last 12 months, Kylie Minogue headlined the pageant, and in 2018 Britney Spears wowed a crowd of 57,000.
Spokesperson for the pageant, Mr Jepson, stated signing Mariah had taken months of planning and organizing.
He added: “She desires to return and do that occasion.
“She acquired the GLAAD award in 2016 so she’s an enormous LGBTQ+ ally and works with the group for acceptance and inclusion. She’s been a good friend of the group for a lot of a few years.
“She’s a global icon, not just for the LGTBQ+ community.”
He stated he didn’t understand how a lot she was being paid for the gig.
Last 12 months the pageant introduced greater than 250,000 folks to the town.
However, environmentalists criticized revelers for the amount of litter left behind, together with a enormous quantity of laughing gasoline canisters.
More than 100 artists can be taking part in on quite a few levels over the three days, and Mariah will play a 75-minute set.
Mr Jepson stated Pride was excited for “everything Mariah can throw at us” and is hoping “she’s going to pull out all the big hits”.
“We’re getting so big now and people want to play our festival, we’re getting people approaching us and asking to do it, which is great,” he added.