Nauert has served as a spokesperson for the State Department since April 2017.
Nauert, 48, previously worked as a host at both Fox News and ABC News before joining the State Department, where she has worked very close under Secretary Mike Pompeo on the road.
Nauert would need to be confirmed by the US Senate, but if she passes that hurdle, she would become a top voice for Trump's foreign policy.
Mr Trump earlier said his daughter, Ivanka, would be ideal for the role but conceded he'd be accused of nepotism if he appointed her.
"What we've really discovered over the last two years is that even when you have a relatively mainstream, relatively collegial, relatively influential ambassador to the United Nations like Haley, that only buys you a limited degree of protection from a president like Trump".More news: Box Office Collection in South India
But she has taken on a bolder role under Pompeo, assertively seeking to promote his message.
At the end of Uri Friedman's interview with her for The Atlantic, the reporter asked Haley what her campaign slogan would be in 2024. Her relative lack of experience for a high-stakes foreign relations position means that Democrats are likely to press Nauert on her qualifications during her confirmation hearings, according to CNN.
Two administration officials confirmed Mr Trump's plans on Thursday.
Because of her inexperience in diplomacy and short political resume, Nauert may face difficulty securing the job.
Unlike Haley, however, Nauert is not expected to have cabinet status, keeping power over foreign policy firmly with Pompeo and especially John Bolton, the hawkish White House national security advisor.
Haley herself arrived at the United Nations with little foreign policy experience beyond promoting global investments in SC. In a sign of the difficulties the administration has had, the UN General Assembly on Thursday rejected a USA -sponsored resolution condemning Hamas, the Islamist group that has ruled the Gaza Strip since 2007. Nauert was then appointed acting undersecretary of state for public diplomacy and public affairs and was for a time the highest-ranking woman and fourth highest-ranking official in the building.
Heather Nauert, 48, has been nominated as USA ambassador to the United Nations, capping a swift rise through the administration's ranks.
"Ms. Nauert has stood by the State of Israel in her previous positions, and I have no doubt that the cooperation between our two countries will continue to strengthen as ambassador to the UN", Israel's UN ambassador, Danny Danon, said in NY.