Joining the Barbadian singer are Erykah Badu, Mary J. Blige, Sheryl Crow, Sugarland, Ke$ha and Selena Gomez.
Rihanna has added her name to music's biggest show of girl power - she'll be part of this summer's Lilith Fair festival tour. The R&B star will make a special appearance at Lilith's Salt Lake City concert in Utah on July 12.
The 36-city tour will commence in Calgary, Canada on June 27 and feature acts including Lilith Fair co-founder Sarah McLachlan, Emmylou Harris, Loretta Lynn, Beth Orton, Erykah Badu, Mary J. Blige and Sheryl Crow.
Rihanna's Lilith date will come during her upcoming Last Girl On Earth North American tour.
Lilith fair itself, which is the first since being absent after 1999, will be kicked off at Calgary's McMahon Stadium and continue until August 10 at Palm Beach's Cruzan Amphitheatre. Other musical guests include Selena Gomez, Ke$ha, Kelly Clarkson and Sugarland.