Earlier in the day, Brazil claimed the bronze medal by beating Slovenia 3-1 (23-25, 25-20, 25-23, 25-19).
Iran, led by head coach Roberto Piazza, finished the tournament in eighth place.
The 2025 VNL was held from June 11 to August 3, with the final match taking place in Ningbo, China.
Historically, Russia and France have each won the VNL title twice in the past seven editions.