Austria's Katharina Liensberger and Swiss skier Michelle Gisin mounted the podium as the runner-up and third-placed skier in the race.
The best Slovakian skier currently leads in the overall standings. She won the Mount Sljeme race last year, too.
The men's slalom race is scheduled for Wednesday.
Both races are organised in compliance with the most stringent anti-COVID measures and without any spectators.
The world's best alpine skiing athletes who are competing in the Snow Queen Trophy in Zagreb on 3 and 6 January and the competition's organiser, the Croatian Ski Association (HSS), will donate HRK 350,000 to areas hit by the December 29 earthquake.