Trump's inaugural committee made the announcement on Wednesday, saying Evancho, 16, "represents the best and the brightest of America."
"I'm so excited. It's going to be awesome," Evancho said on the "Today" show on Wednesday.
Celebrity news website TMZ reported on Wednesday that Italian tenor Andrea Bocelli would also be singing at the Jan. 20 ceremony, but there was no official confirmation.
As a tiny 10-year-old, Evancho wowed Americans with her soaring soprano on classical arias like Puccini's "O mio babbino caro," taking second place on "America's Got Talent." She will follow in the footsteps of Aretha Franklin and Beyonce, who performed the "The Star-Spangled Banner" at President Barack Obama's two inaugurations.
After her "America's Got Talent" run, Evancho became the youngest solo artist to have a platinum-selling album in the United States. She met Trump at that time and has a photo on her Facebook page of the two of them standing together.
The inaugural committee has said it has "world-class talent" offering their services for the ceremony, but Evancho is the first celebrity to be announced.
The inaugural committee's chairman, Tom Barrack, quashed speculation on Tuesday that rapper Kanye West, who had a surprise meeting that day with the Republican president-elect at Trump Tower in New York, would be performing.
Country singer Garth Brooks is in discussions to perform, and, according to celebrity media, other names thought to be in talks include Kid Rock, rocker Ted Nugent and country star Lee Greenwood.
Beyonce, Katy Perry, Bruce Springsteen and many other leading music stars backed Democrat Hillary Clinton in the election, and Elton John last month denied a report that he would be playing for Trump.
Banner image credit: Reuters