The nod could spark questions about potential conflicts of interest, given Isaacman's extensive financial ties to Elon Musk, who is set to co-chair a government efficiency commission and is one of Trump's closest advisors.
Isaacman, 41, the founder and CEO of Shift4 Payments, has emerged as a leading figure in commercial spaceflight through his high-profile collaborations with Musk's SpaceX.
His achievements include stepping out of a Crew Dragon to gaze at Earth from the void of space, while clutching the spacecraft's exterior, back in September.
"I am delighted to nominate Jared Isaacman, an accomplished business leader, philanthropist, pilot and astronaut, as Administrator of the National Aeronautics and Space Administration (NASA)," Trump wrote on Truth Social.
"Jared will drive NASA's mission of discovery and inspiration, paving the way for groundbreaking achievements in Space science, technology, and exploration."
The historic spacewalk took place under the Polaris program, a collaboration between Isaacman and SpaceX that is set to include three missions in total.
Financial terms of the partnership remain under wraps but Isaacman reportedly poured $200 million of his own money into leading the 2021 all-civilian SpaceX Inspiration4 orbital mission, his first foray into space.
He is also a vocal supporter of SpaceX and Musk, frequently praising the company and its vision on the platform X.
"There will inevitably be a thriving space economy -- one that will create opportunities for countless people to live and work in space," Isaacman said in a post after Trump's announcement.
"At NASA, we will passionately pursue these possibilities."
Isaacman, a Pennsylvania native, founded the business that became Shift4 Payments from his family's basement at just 16.
A skilled aviator, he is qualified to fly military aircraft, has performed in airshows, and set a world record for an around-the-world flight.
