Salar Aghapour, Saeid Ahmad Abbasi and Mohammad Hossein Derakhshani scored for Iran.
Iran will play the winner of Morocco and Finland in the final on Friday.
The tournament is hosted by the Football Association of Thailand (FAT) from September 11 to 16 in Bangkok, Thailand.
Iran has competed in the Tournament as part of preparation for the 2022 Asian Futsal Championship that will take place from September 25 to October 20 in Kuwait.
Team Melli has been drawn in Group C along with Lebanon, Chinese Taipei and Indonesia.