The four-time Grand Slam champion from Italy will replace six-time major winner Carlos Alcaraz at the top if he wins Sunday's final against the ninth seed, Felix Auger-Aliassime, who needs a win to clinch the eighth and final spot for the season-ending ATP Finals in Turin, Italy.
Earlier on Saturday, Auger-Aliassime earlier beat Alexander Bublik 7-6 (7-3) 6-4 in their semi-final at La Defense Arena.
Sinner extended his indoor winning streak to 25 matches, including a victory over Zverev in the Vienna final last weekend. He beat Zverev — the defending champion in Paris — for the fourth straight time to lead 5-4 in their career meetings.
Sinner was 5-0 up in 25 minutes and then served out a first set in which he won 90% of his first-serve points, compared with only 47% for Zverev. He had five break points on Zverev's serve, converting two of them.
In the second set, Sinner broke Zverev for a 2-1 lead. The third-seeded German looked drained and stood with his hands on his knees after that game.
Zverev had saved two match points to beat Daniil Medvedev in three sets in their gritty quarter-final on Friday to end a five-match losing streak against the Russian.
Sinner will bid for his fifth title of the year, and 23rd of his career, on Sunday; Auger-Aliassime, meanwhile, will be aiming for his fourth of the season and ninth overall.
They are 2-2 in head-to-heads, with Sinner winning the past two — including in the semi-finals at this year's US Open.
Bublik led 4-1 in the second set but then lost five consecutive games, smashing his racket on the ground after one of them.
Serving for the match, Auger-Aliassime began with his 12th ace. A forehand winner at the net gave him a first match point and he clinched it with another big forehand. Auger-Aliassime patted his heart and waved to the crowd.
