English pop rock band The Feeling and rock bands The Zombies and Big Country are also part of the line-up revealed for Friday July 25.
Motown legends Martha Reeves And The Vandellas will be appearing as part of their tour to mark the 50th anniversary of their biggest hit Dancing In The Street.
The festival takes place at East Kirkcarswell Farm, Dundrennan in Dumfries and Galloway, where the classic 1973 Wicker Man film was made, the inspiration for the festival's name.
It culminates with the burning of a 40ft wickerman.
The festival's co-ordinator, Helen Chalmers, said: "We are delighted that Dizzee Rascal will be joining the party this year, his live performances are incredible and I can't wait to see the crowd's reaction to his headline set.
"From hip hop, pop, folk to motown and alternative rock, this year's line up will once again be a truly diverse offering and we look forward to announcing further exciting additions including our Saturday night headliner over the coming weeks."
The independent Wickerman festival is now entering its 13th consecutive year and has 10 stages featuring a mixture of leading artists, alternative acts and up-and-coming talent.
Best known for his number one hits Dance Wiv Me, Bonkers, Holiday, Dirtee Disco and Shout, Dizzee Rascal is an English MC, songwriter and record producer with Ghanaian and Nigerian roots.
His debut album Boy In Da Corner won him the 2003 Mercury Prize.
The Zombies will perform some of their 1960s hits, such as She's Not There while organisers said that Big Country will add a Scottish touch to proceedings. This year will mark the 30th anniversary of their classic album Steeltown.
The bands Finding Albert, from Dumfries and Galloway, and Model Aeroplanes, from Dundee, will also play at the festival which runs from 25-26 July.