The British journalist - one of the talent show's original judges - left the series in 2011, but will join the current panel of Howard Stern, Mel B, Howie Mandel and Heidi Klum in a guest role later this season, reported People magazine.
The 50-year-old tweeted the news ahead of "America's Got Talent" season 10 premiere on May 26 on NBC.
He also joked alongside a corresponding picture: "What made me go back on @nbcagt? Well, @heidiklum & her bullhorn were pretty compelling reasons."
Morgan was a judge on "America's Got Talent" between 2006-11, after judging "Britain's Got Talent" from 2007-10.