NBC has announced Klum will join returning judges Howard Stern and Howie Mandel and recently-announced new judge Melanie Brown -- the former Spice Girls member and Dancing with the Stars participant commonly known as "Mel B" -- on the show's panel this summer.
"America's Got some serious Talent! I'm really excited to join the panel of AGT to see it all -- from the ridiculous to the fantastic!" Klum said in a statement. "I love the surprise element of the show and not knowing what we'll see next and who will wow us. I'm also looking forward to spending time with my fellow judges - Howard Stern, Howie Mandel and Mel B!"
The addition of the Project Runway host and supermodel marks the first time in America's Got Talent history the show will feature four judges. Klum and Brown are replacing Sharon Osbourne, who chose to leave the reality talent competition at the conclusion of last season.
"Heidi has an amazing career across multiple media platforms, and has built a brand that is a force in the entertainment business," added NBC reality chief Paul Telegdy.
"She has achieved superstardom while balancing being a businesswoman and hard-working mom, bringing a huge amount of experience, discernment and taste to the panel. As we look to develop an act that will get the world's attention, we and the contestants will benefit from Heidi's international sensibility and understanding of what works in today's global entertainment industry."
The network announced Brown's participation late last month. She competed on the fifth season of ABC's Dancing with the Stars in 2007, finishing second with professional partner Maksim Chmerkovskiy.
After starring in Mel B: It's a Scary World, a reality series which aired on the Style network in 2010, Brown served as a judge on the last two seasons of Australia's edition of The X Factor and co-hosted last year's Australian edition of Dancing with the Stars.
Stern joined the show as a replacement for Piers Morgan last year while Mandel was added to the panel in 2010 as a replacement for David Hasselhoff.
Osbourne announced she was quitting America's Got Talent in August after NBC allegedly dropped her son Jack Osbourne from the cast of Stars Earn Stripes -- a physically-arduous, military-themed reality competition the network aired late last summer -- after he disclosed he has multiple sclerosis. NBC has denied the discrimination claim.