Reality TV
The singer, who won the talent search in 2003, will perform a cover of Kenny Loggins's 'Celebrate Me Home'.
The track will play as the contestants are eliminated from the live shows, which begin on March 11.
Terry Lewis, who co-produced the song with Jimmy Jam, said: "It's very soulful, very heartfelt. Ruben is singing his pants off."
It will also be available on the internet from March 12 as part of the show's sponsorship deal with iTunes.
19 Entertainment head Ian Pirie said Studdard had been chosen after he received a rousing reception during an appearance on last season's finale.
Daniel Powter's 'Bad Day' sold 1.9 million copies in the US after it was used as the farewell song in the fifth season.
Studdard, 29, was axed by J Records last December.
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