Ali Hajipour and Pouriya Hossein Khanzadeh scored 20 points apiece for Iran, while Lorenzo Pope scored 18 for Australia.
Team Melli will play winners of Japan and South Korea in the final match on Sunday.
The winning team will earn a direct quota place for the 2028 Summer Olympics, while the top three finishers will secure qualification spots for the 2027 FIVB Men's Volleyball World Cup.
MNA