Eustace, 57 was lifted aloft from an abandoned runway Friday at the airport in Roswell, New Mexico, by a balloon filled with 35,000 cubic feet of helium.
For a little over two hours, the balloon ascended at speeds up to 1,600 feet per minute to an altitude of more than 25 miles.
Eustace dangled underneath in a specially designed spacesuit with an elaborate life-support system.
He returned to earth just 15 minutes after starting his fall.
"It was amazing. It was beautiful. You could see the darkness of space and you could see the layers of atmosphere, which I had never seen before," he said.
Eustace cut himself loose from the balloon with the aid of a small explosive device and plummeted toward the earth at a peak speed of 822 miles per hour, setting off a small sonic boom heard by people on the ground.
The previous altitude record was set by the Austrian Felix Baumgartner, who jumped from 128,100 feet Oct 14, 2012.
Eustace said that Google had been willing to help with the project, but he declined company support, worried that his jump would become a marketing event.