The Slovenian's fourth win of the season put her on 677 points, ahead of Germany's Maria Hoefl-Riesch by 234 points while American Lindsey Vonn lies third, a further 29 points behind.
Maze, the giant slalom world champion, clocked two minutes 11.07 seconds to upstage Olympic champion Vitkoria Rebensburg by 0.08 seconds while France's Tessa Worley was third, 0.55 adrift.
Maze had won Friday's super-combined in St Moritz before finishing just behind Vonn in Saturday's super-G on the same course.
Vonn, who has never been at her best in giant slalom, was fifth after Sunday's first leg but crashed in the afternoon run and ended up 27th.
"I came here hoping to win three races and I did more than half the job," Maze told reporters.
"Two out of three is not bad but I was really looking forward to the super-G because I have never won in this discipline. I know it's not over but I like it when I stick to my plan."
Vonn said: "I did everything I could today and I had the impression I skied well. I'm sorry to finish like this because I know I could have done much better but now I don't have anything left in me."
The weekend struggle between Maze and Vonn heated up after Saturday's race when the Slovenian team issued a protest, saying the American had sworn at her rival after crossing the line with the fastest time.
The protest was rejected and Vonn proclaimed her innocence again on Sunday, telling Reuters: "Those who know me know it's not my style."
Maze declined to comment on the row, adding: "It's true that I'm pushing hard but the battle is more with myself. It did not start in St Moritz, I've been working like crazy for years and since June I've left nothing to chance. It's not a ruthless win, it's just the result of hard work."
The women's circuit moves to Val d'Isere in France next weekend for a super-G and a downhill in which Vonn will try to stretch her unbeaten run in speed events.
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