Vonn, who scored a hat-trick of wins at Lake Louise last weekend in the speed disciplines, took the giant slalom honors at Are in Sweden to continue her domination of the 2015-16 season.
But teammate Mikaela Shiffrin, one of her main rivals for overall World Cup honors, saw her hopes dashed by a knee ligament injury after a crash during the pre-race warmup.
Shiffrin, who was hot favorite to win Sunday's slalom event in Are after taking the opening two slalom events of the season, instead was flying home to the United States for further tests on a worrying knee ligament injury, she posted on her Facebook page.
"I have at least (an) MCL injury and bone bruising, hopefully no additional injury," she said, but her participation in remaining events in 2015 is in serious question.
There was also a setback for American Ted Ligety in the men's giant slalom in Val d'Isere.
Ligety, nicknamed Mr GS for his domination of the discipline, skied out on the first leg after a mistake.
Troubled by a back injury, Ligety also posted a "did not finish" at Beaver Creek last week and has only one podium finish in six starts.
It left the way clear for Austria's Marcel Hirscher to claim victory, adding to his two in Colorado.
Felix Neureuther of Germany took second, with France's Victor Muffat-Jeandet completing the podium, both men over a second adrift over the two legs.
Victory saw Hirscher leapfrog Norway's Aksel Lund Svindal in the standings as he bids for a fifth overall World Cup title and he further boosted his chances with an excellent second place in Sunday's first slalom of the season behind winner Henrik Kristofferesen of Norway of Norway.
Hirscher made up ground with a superb second run, but was 1.09 second the 21-year-old winner. Neureuther finished third.
Vonn is also eying a fifth overall crown and gave her cause another boost with a narrow victory -- just 00.70secs faster than Eva-Maria Brem of Austria and 00.35secs ahead of third-placed Federica Brignone of Italy.
She has a 104-point lead over Shiffrin in the overall standings after her 71st World Cup win from 347 starts.
She had won a GS at Are in 2012 and used it to good effect.
"I watched playback of that win yesterday evening and I had plenty of confidence coming out of Lake Louise," she said.
Vonn did not compete in Sunday's slalom, her weakest discipline and with Shiffrin, winner of seven of the last eight World Cup slaloms also missing, the way was clear Petra Vlhova of Slovakia to claim her maiden victory on the circuit.
Home hope Frida Hansdotter of Sweden finished second, but takes over from Shiffrin at the top of the slalom standings. Nina Loeseth of Norway finished third.
"It's an amazing day for me,"the 20-year-old Vlhova told the official FIS website.