The previous winner was Felix Baumgartner who made a supersonic parachute jump to earth from a space balloon.
A record 75,000 people cast online votes to determine the 2014 victor from a line-up of alpinists, long-distance swimmers, educators and community builders.
Jornet draws on his talents in a number of fields, including trail running and mountaineering, to push the limits of human ability as a 'skyrunner', a sport that involves going up technically challenging terrain at a runner's pace.
He hit the headlines last year when he conquered the iconic peaks of Mont Blanc and the Matterhorn in record time.
His combined ascent and descent of Mont Blanc involved an elevation change of 12,378 feet in under five hours.
He then ran up and down the Matterhorn in under 3 hours, a route that takes most experienced climbers about 12 hours.
The challenges were part of his personal 'Summits of My Life' project in which he takes on the world's toughest mountains.
Since starting as a skyrunner aged 17, he has won the world championship four times.
Jornet grew up in the Spanish Pyrenees as the son of a mountain guide and began racing in ski mountaineering when he was 13.
He told National Geographic: " "I am a person that loves mountains. I can go with skis when there's snow, and I can go running when it's summer. Doing all this stuff – it's the possibility to live in the mountains and to live my passion. It doesn’t really matter if I win or whether I finish last. It’s important maybe for me, but it really doesn’t matter."
Upon receiving the award he said, "The most exciting thing is that this prize comes from the people, so I want to thank everyone who has voted for me and everyone who has supported me since I started on this. To feel that what I do can inspire someone, that it makes them go out in a quest for their dreams, that's what really matters.”
"It's a great honor," he added. "I don't run or make these records for the recognition, but it is nice to receive a prize where the people have voted for me."