The 'We Found Love' star was due to perform at the event on Thursday (July 5), but has pulled out of her headline slot to mourn the loss of Clara 'Dolly' Braithwaite, who lost her battle with cancer at the weekend.
Organisers of the festival have apologised to fans and offered to refund tickets. They are currently searching for a last-minute replacement.
Rihanna is due to headline Wireless Festival in London on Sunday (July 8), which is still scheduled to go ahead.
Swedish fans had previously criticised her lacklustre set at the Peace and Love festival, before her grandmother's death came to light.
Some described her performance as "disgusting and shameful", while others claimed she appeared to be drunk and forgot which country she was in.
The singer has been posting a series of tributes to her grandmother online, sharing family photographs with fans.
Watch Rihanna's video for 'We Found Love' featuring Calvin Harris below: