The 20-year-old Estonian had already secured the 2021/2022 crystal globe on Thursday, with Switzerland's Sarah Hoefflin - second in the general rankings - finishing 9th in qualification and missing the cut for the final.
On a sunny day with perfect conditions, Sildaru continued her perfect record claiming her third win out of three events she entered this season.
A flawless first run earned her 88.25 points, which ended up being highest score of the day and made her second attempt just a victory lap.
The six-time Winter X Games gold medallist finished in front of 2017 world champion Tess Ledeux of France (80.50), while Johanne Killy of Norway pipped Britain's Katie Summerhayes for third place (79.25).
"It's been a crazy season. This season started well for me and is ending even better," said Silderu, who also triumphed in Stubai, Austria, in November and in Mammoth Mountain, USA, early this January.
The crystal globe caps a spectacular season for the 2020 Youth Winter Olympics gold medallist, whose bronze at Beijing 2022 in February was her nation’s first-ever Olympic medal in freestyle skiing.
Ruud wins overall World Cup globe
Olympic big air champion Birk Ruud won the men's event to clinch the Overall Park&Pipe title.
The 21-year-old Norwegian claimed his third slopestyle event of the season, the eighth overall.
"It's been a long season with Olympic gold and a lot of competitions, and to finish on top...I don't know what to say, but I worked hard, when you work hard and smart it pays off," he said.
Ruud stomped a 94.50 in the first run to beat Mac Forehand (91.75) and reigning world champion Andri Ragettli (90.00), who sealed the slopestyle globe for the fourth time.