The 68-year-old performer, who is most well known for hits 9 to 5, Islands in the Stream and I Will Always Love You will sing for the wellie-wearing festival goers as part of her Blue Smoke World Tour, which comes to Europe on 8 June.
Debbie Harry of iconic 70s band Blondie has also confirmed that the group will be appearing at the festival.
The 68-year-old star said, “We just heard today – we’re going to be doing Glastonbury” at last night’s NME Awards, where she performed and accepted NME’s godlike genius award.
Glastonbury Festival will be on between 25 and 29 June 2014.
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