Navid Taheri Rad (three goals), Zabihollah Rahchamani (two goals), Mohammad Ali Salehipour (two goals), Aref Hamedi (two goals) and Mohammad Reza Saadat scored goals for Iran.
Kinutani Ryusuke scored Japan’s only goal.
Iran has previously defeated Hong Kong 7-2, Indonesia 5-2, Kazakhstan 12-8 and Afghanistan 12-2 in the Challenger Pool.
Team Melli will play Malaysia later today.