Robert Karlsson and Stenson birdied the first hole and added eight more without dropping a shot to lift Sweden to its second World Cup title, shooting a 9-under 63 in alternate-shot play to beat Spain's Miguel Angel Jimenez and Pablo Larrazabal by three strokes.
Karlsson and Stenson, four strokes behind the Spaniards after the third round, finished at 27-under 261 on Mission Hills' Olazabal Course.
Germany opened with a 62 on Thursday, Spain carded 63 on Friday and Australia added its own 63 on Saturday.
"I figured it could be ours on Sunday," Stenson said. "I thought it was our turn."
Sweden's only other victory in the event came in 1991 when Per-Ulrik Johansson and Anders Forsbrand beat Wales by a stroke at Le Querce in Rome.
Jimenez and Larrazabal finished with a 70 in their bid to give Spain its fifth title and first since 1984. Australia's Richard Green and Brendan Jones (76) and Japan's Ryuji Imada and Toru Taniguchi (68) tied for third at 18 under. Americans Ben Curtis and Brandt Snedeker (73) finished ninth, 14 strokes back at 13 under.
The victory caps a great season for Karlsson, a two-time winner on the European tour and the tour's top money winner. Stenson is winless this season in individual play.
"I'm starting to run out of tournaments," he said. "This is my third last. So, I've got two more to go in South Africa. But winning for Sweden in nice. It's been a while."
The key was Sweden's mastery of the difficult foursomes (alternate shot) format, played Friday and Sunday. In foursomes, teams play only one ball and alternate shots. In fourball (best ball), each golfer plays his own ball and the best score on each hole is counted.
Sweden shot 67-63-130 playing foursomes and 65-66-131 playing fourball.
In the Ryder Cup three months ago, the two Swedes teamed up in fourball but not in foursomes.
"There's always Wales 2010, isn't there," Stenson said, pointing to the next Ryder Cup.
Karlsson said the foursomes format might suit him best, particularly after a long season and a so-so round on Saturday.
"I was especially pumped up for this today," he said. "If you're a little bit tired at the end of the season, you only have to hit half as many shots. It's a bit easier to focus as well, and foursomes is more challenging."
The Swedes made five birdies on the front nine to catch the Spaniards at 23 under. Playing a group ahead of Spain, Stenson missed a short birdie putt on 10 that would have put them at 24 under.
Sweden pulled into the outright lead with birdies on Nos. 11, 12, 14 and 15 to reach 27 under four clear of Spain. Stenson missed a 10-footer on No. 13 that would have extended the lead even more.
The Swedes were the favorites entering the tournament, and had two of only three players in the field ranked in the top 20. Karlsson is No. 6 and Stenson 12th. Spain's Jimenez is ranked 20th.
All four days were played in perfect conditions with a light breeze stirring through the hilly, tree-lined course designed by two-time Masters champion Jose Maria Olazabal. The rolling layout looks familiar, with only a 100-foot-high stone statue of Guanyin along the 18th fairway a Chinese female goddess with Buddhist origins suggesting the club's location.
The Swedes split $1.7 million in prize money, a big chunk of the $5.5 million purse. Despite the global economic downturn, the purse offered by sponsor Omega was 10 percent above last year. This year's event was the second of a 12-year contract at Mission Hills, the sprawling golf estate that boasts the world's largest layout with 216 holes.
Dating from 1953, almost every great player has won the event Palmer, Nicklaus, Hogan, Snead, Woods and Ballesteros. Though it's still failing to attract a top field, it's being given an economic boost by its sponsor and Mission Hills chairman and founder Dr. David Chu.
"I just hope this tournament can keep getting better over the years," Karlsson said.