Reality TV
The X Factor presenter will front the live eviction shows for the series, which kicks off in January.
The programme will feature famous names taking on the role of Big Brother, while a group of "extremely talented but ordinary" 18 to 21-year-olds compete for a £50,000 prize.
Channel 4 also confirmed that Davina McCall will present the ninth series of Big Brother next summer.
Head of E4 Angela Jain said: "Dermot is a pivotal part of the Big Brother team so it's appropriate he's at the helm. We're are also thrilled Davina will be returning."
Celebrity Hijack replaces this year's celebrity version of the show, which has been given a break from its annual scheduling.
More: Reality TV, Big Brother
Related Stories
Tube Talk
TV's Biggest Bitches: Friday FiverOur picks for the five biggest bitches on both sides of the Atlantic.
TV Interviews
Apprentice Gabrielle 'was easy target'Digital Spy talks to Gabrielle Omar about being too nice for the show.
TV Ratings
Grandma's House rises for final episodeLong Lost Family's resilience helps ITV score another primetime victory.
TV Recaps
'Homeland' finale: Have your sayHomeland's incredible finale is reviewed by Digital Spy. Share your verdict.
