Stern confirmed rampant rumours that he planned to join the NBC reality series on his Sirius XM radio show on Thursday (December 15), when his agent Don Buchwald presented him with his America's Got Talent contract on the air.
America's Got Talent will move its live shows from Los Angeles to New York to accommodate Stern's morning radio schedule.
The controversial radio host vowed to lead fellow judges Sharon Osbourne and Howie Mandel in finding America's next great superstar.
Stern said: "This nonsense of Howie and Sharon putting through less-than-talented people has got to stop. Under my administration there will be no Frank Sinatra impersonators winning for the year.
"If people think I'm the crazy man, I am not. I am the voice of reason… Goofy acts are not going through."
Stern also said that he will emulate former America's Got Talent judge Morgan, who was known for being harsher than Osbourne and Mandel.
"I'm going to be Piers [Morgan] on steroids," Stern vowed. "It's going to be a no-nonsense judge... I'm going to go there as a serious judge... It's gonna be something else... I am very excited."
NBC also confirmed Stern's hiring on Thursday, with the Peacock Network's president of late-night programming Paul Telegdy welcoming Stern to the NBC family.
Telegdy said: "Howard Stern's larger-than-life personality will bring a thrilling new dynamic to America's Got Talent starting this summer.
"He's a proven innovator and his track record in broadcasting is truly remarkable. Howard is very passionate about this show and is fully committed to its future success."
Stern previously worked as a radio host for NBC, but was famously fired for being too controversial in 1985.
America's Got Talent judge Mandel reacted to the news by tweeting: "I cannot wait. Let the judging begin... Welcome to the party [Howard Stern]."
As rumblings of his America's Got Talent hiring began in November, Stern suggested that he was the ideal choice to replace Morgan because of his 30 years of experience in the entertainment industry.
America's Got Talent co-creator Simon Cowell publicly backed Stern for the role, saying: "Howard brings a kind of chaos to everything. But I like chaos."
Reports of Stern potentially joining America's Got Talent drew protests from moral values group the Parents Television Council, who accused NBC of desperation for even considering the radio host.
His predecessor Morgan departed America's Got Talent last month in order to focus on his CNN chatshow.
America's Got Talent returns to NBC in the summer of 2012.
> Howard Stern might not be good AGT judge, says Nigel Lythgoe
> Sharon Osbourne: 'Piers Morgan America's Got Talent exit really sad'