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: TV, Big Brother
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