The 28-year-old German player performed well against Musetti to notch up his 300th win on hard courts.
After breaking the Italian fourth seed in the 11th game of the second set, he played well in key points in the serve game without making any mistakes.
Since losing to Sinner at the Australian Open, Zverev has reached just two more finals, winning on clay in Munich in April and losing on grass in Stuttgart in June.
This is in stark contrast to Sinner’s record, with the Italian world number two becoming the first man since Novak Djokovic in 2015-16 to reach eight finals in consecutive seasons.
Sinner extended his winning streak on indoor hard courts to 20 matches and went on to a 12-match unbeaten run against Australian third seed De Minaur and a fourth straight win at ATP 500 events.
He was broken twice – once in each set – but fought hard in what he described as a “physical” encounter.
“I’m happy with the way I handled it,” said the 2023 Vienna Open champion, who is aiming for a fourth title of the season after winning at the Australian Open, Wimbledon and China Open.
“I got picked up in the second game and he knocked me down again. I tried to stay mentally strong so I’m really happy with my performance today and obviously I can play in the final again.”
In addition, 19-year-old Brazilian Joao Fonseca defeated unseeded Spanish player Jaume Munar 7-6 (7-4) 7-5 at the Swiss Indoors in Basel and reached the ATP 500 final for the first time in his career.
He will face another Spanish player, Alejandro Davidovich Fokina, in the final after eighth-seeded Frenchman Ugo Humbert withdrew in the semi-finals after trailing 7-6 (7-4) 3-1.
