The Swiss enjoyed a faultless weekend at the French alpine resort.
After pipping Vonn by 0.01 seconds to the clinch the super-combined title on Friday, Gut followed up with another flawless display in the downhill with Vonn nowhere to be seen this time.
The American, who was looking to equal Austrian legend Annemarie Moser-Proell's record of 36 downhill wins ended up skiing out of the race after narrowly avoiding a potentially heavy fall.
Riding a bump midway down the course, Vonn was forced off balance, her left ski flicking up to the side. Somehow, the 31-year-old managed to stay upright and unscathed, but her race was over.
With her main challenger out of the running, Gut took full advantage eventually winning by 0.16 seconds from compatriot Fabienne Suter. Canada's Larisa Yurkiw was third.
"This is my third win in Val d'Isere and it's not by chance. This race is a bit of fresh air for me. I feel good here," Gut said after the race.
Gut's 15th World Cup victory of her career means she moves to within two points of Vonn at the top of the Overall leaderboard — with 478 points to the American's 480.
The women's World Cup tour heads to Courcheval on Sunday for the giant slalom.
Mayer crash mars Svindal win
Olympic downhill champion Matthias Mayer was airlifted to hospital after crashing out of the men's downhill event at Val Gardena, Italy on Saturday.
The Austrian suffered a heavy fall which saw his safety airbag inflate -- the first time the safety equipment has deployed during a race.
Mayer was conscious as he was airlifted off the slopes, according to reports
The event was won Aksel Lund Svindal who completed a brace of wins in the men's World Cup races at Val Gardena -- the Norwegian won the Super G race on Friday.
Svindal finished 0.43 seconds ahead of France's Guillermo Fayed with Svindal's compatriot Kjetil Jansrud finishing third.
The victories extend Svindal's lead over Austria's Marcel Hirscher at the top of the Overall standings to 77 points.