Seavey, 25, who was cheered across the Nome finish line by spectators, family and friends, said the last 30 miles were tough, the Anchorage Daily News reported.
"I got to see a lot of wind," he said. "It's a tough way to finish the race, but it makes us appreciate how tough the Iditarod is and why it's the Last Great Race on Earth."
The Willow musher finished in 9 days, 4 hours, 29 minutes, 26 seconds.
Aliy Zirkle, 41, of Two Rivers, who had led for about 300 miles of the race that began in Willow near Anchorage, was poised to finish second, the Daily News said. Ramey Smyth was in third place about an hour behind Zirkle and 2 hours behind Seavey, the newspaper said.
For his effort, Seavey will take home $50,400 in prize money and the keys to a new truck.
Before Seavey's victory, the youngest winner had been Galena's Carl Huntington, who won in 1977 at 26 years old. Seavey's father Mitch won the race in 2004.