The year-long tie-up marks the first time the breakfast show has been sponsored. The deal includes sponsorship of the Century Network breakfast show and will see Kellogg-branded trails and promotions feature in other shows across both networks.
Kellogg's UK marketing director Michael Allen said: "The sponsorship offers us a great opportunity to reach Kellogg's Corn Flakes consumers during breakfast and continue to be a part of people's morning routine."
Capital has kept details of its new breakfast show tightly under wraps after receiving a battering from the press for falling figures for the existing show and rumours that presenter Chris Tarrant was about to quit.
But the station pulled off something of a PR coup by announcing in September that Tarrant had agreed to stay on and relaunch the show - albeit with a contract that allows him to start later, at 7 am and to take more holiday.
Neil 'Dr' Fox will deputise for Tarrant when he's absent. Capital has also announced that Newsround's Becky Jago will join the show.
The deal was negotiated by Broadmind, the sponsorship division of MindShare and by Capital Radio Group's sponsorship team.
The tie-up with Capital is the latest in a series between Kellogg and media owners. Earlier this year Kellogg linked with Cartoon Network in a deal that saw characters such as Johnny Bravo and The Powerpuff Girls replace on-pack characters Snap, Crackle and Pop and Tony the Tiger.