Vonn edged up-and-coming French star Marie Marchand-Arvier by 0.34 seconds on the opening day of the World Championships at Val d'Isere.
Vonn covered the course in 1:20.73 while the 23-year-old Marchand-Arvier was runner-up at 1:21.07. Andrea Fischbacher of Austria was in third-place at 1:21.13.
The win came off a solid weekend performance for Vonn, who had two wins at the Audi World Cup event in Germany that included her first super G win in two years. The Colorado-based veteran will take part in the downhill, slalom and super combined later in the week.
The World Championships resume Wednesday with the men's super G race and training runs for the women's downhill.