Santogold, Alice Smith, Saul Williams, Holt Melts, Tinnie Tempah and Annie will play on the Thursday alongside Jay-Z and Mark Ronson.
Joining Morrissey and Beck on the Friday are The Wombats, Black Kids, Get Cape Wear Cape Fly, The Whigs, Peter and The Wolf and The Hosts.
Added to Saturday's lineup alongside Fatboy Slim and Bootsy Collins are 'Brimful of Asha' rockers Cornershop, Audio Bullys, Caged Baby, MSTRKRFT and Japanese Pop Stars.
Rounding off the weekend on Sunday with Counting Crows and Goo Goo Dolls will be Joe Purdy, Magic Christian, Ryan Shaw and Glactica.
The summer bash takes place at London's Hyde Park on July 3-6. Tickets are still available.