Harrison, who hosted last year's ceremony alongside Dancing with the Stars's Brooke Burke, will front the pageant live from the Planet Hollywood Resort & Casino Las Vegas on Saturday, January 14 on ABC.
He said: "It is an honour to come back and host Miss America for my third time and second year in a row.
"Hosting Miss America is one of the most iconic hosting jobs in television, so I am of course thrilled to once again be at the helm. I was extremely pleased to see the pageant return to network TV last year with so much success, and I was happy to be a small part of that."
Miss America Organisation's Board Chairman Sam Haskell III said: "We're thrilled that Chris is returning to host the 2012 Miss America Pageant. Chris did a wonderful job for us last year as we celebrated our 90th anniversary with record ratings, and we are honoured to have him return for another incredible television event."
Art McMaster, the president and CEO of Miss America Organisation, added that Harrison is "the perfect choice" to front the broadcast.
"Chris understands the depth of our programme and he helped successfully set the stage to spotlight 53 incredible young women competing," he said in the press release. "We are proud to have him host our pageant again and know that he will add his talents to the production to have another winning telecast."
Miss Nebraska Teresa Scanlan was named Miss America during last year's ceremony, with Miss Arkansas Alyse Easy taking the first runner-up spot and Miss Hawaii Jalee Fuselier securing second runner-up.
2012 Miss America Pageant airs Saturday, January 14 at 9pm ET on ABC.
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