Suzuka, Japan – Despite McLaren's Jenson Button winning the to-back world championships with a third- lap race.
Vettel, with nine wins already this season, needed only one point to clinch the title. The 24-year-old German started on the pole and led until his second pit stop on lap 19. Button pitted one lap later and came out ahead of Vettel to lead for good.
Button finished 1.16 seconds ahead of Ferrari's Fernando Alonso, while Vettel crossed the line two seconds behind the winner to secure the title with four races to go.
Vettel has accumulated 324 points compared to Button's 210. He became the ninth different driver to win consecutive world championships. Alonso was the last one to do it, winning his titles in 2005 and '06.
"To win the championship here is fantastic," a jubilant Vettel said after his podium finish in the Japanese GP. "There are so many things I want to say in this moment, but it's hard to remember all of them. I'm so thankful to everyone in the team. They pushed hard to build those cars. It's great to achieve the goal we set ourselves already, with four races left."
Button, the 2009 F1 titleholder, claimed his third victory of the season and the 12th of his career.
"This circuit is very special to all of us, so to get a victory here in front of this Japanese crowd means a lot," he said.
Button's win helped McLaren remain alive in the F1 constructors' championship standings. Red Bull has 518 points to McLaren's 388.
Alonso overtook Vettel for second in the late stages of the race and then challenged Button for the lead during the closing laps.
"From the start, we didn't overtake any car, but then the strategy was quite important, with a lot of tire degradation, so we picked the right moment to stop, and we had the pace today to fight with McLaren and Red Bull," Alonso said.
Vettel has finished on the podium for every race this season, with the exception of the German Grand Prix, where he finished fourth.
"Today's race was not so easy," he said. "I think we were not that quick on the soft tires as we hoped to be, and then it was difficult. We lost two positions."
Vettel's teammate, Mark Webber, finished fourth, followed by Lewis Hamilton from McLaren and Mercedes GP driver and record seven-time F1 champion Michael Schumacher.
Ferrari's Felipe Massa took the seventh spot, while Sergio Perez from Sauber and Lotus Renault GP's Vitaly Petrov finished eighth and ninth, respectively.
Nico Rosberg from Mercedes completed the top-10 after starting from second-to- last. Rosberg did not participate in Saturday's qualifying session due to a hydraulic problem with his car.