Iran’s Seyed Matin Hosseini collected 18 points, while Tommaso Barotto of Italy scored 14 points.
In the 2023 edition held in Manama, Iran had defeated Italy 3-2 in the final.
It was Iran’s ninth win in the competition as the young Persians had defeated Kazakhstan, Puerto Rico, South Korea, Canada, Poland, Argentina, China and the US in the competition.
Earlier in the day, the US eased past Czech Republic 3-0 (25-20, 25-19, 25-18) in the bronze medal match.
The competition was held in Jiangmen, China from August 21 to 31.
The 2025 FIVB Volleyball Men's U-21 World Championship was the 23rd edition of the tournament, contested by men’s national teams under the age of 21 who are members of the Fédération Internationale de Volleyball (FIVB), the sport’s global governing body.