Maze turned in a combined-run time on the St. Moritz course of 2 minutes, 11.07 seconds, edging second-place Viktoria Rebensburg of Germany and Tess Worley of France.
The win gave Maze a commanding 234-point lead in the overall standing over Germany's Maria Hoefl-Riesch and Lindsey Vonn of the United States.
"She's skiing amazing right now," Vonn said. "I really have my work cut out for me in tech events.
Vonn, battling fatigue and stiff winds on the course, was in contention after the first run Sunday but nearly crashed on her second attempt and finished in 27th place. Teammate Julia Mancuso came in 21st.