Milad Ebadipour scored 14 points for Iran and Mayu Ishikawa had 14 points for Japan.
Iran lost to Brazil 3-2 and defeated Argentina 3-1 in Tokyo.
The 2019 FIVB Volleyball Men's Nations League is the second edition of the FIVB Volleyball Men's Nations League, an annual international men's volleyball tournament contested by 16 national teams.
Team Melli will host Canada, Russia and Poland in Oroumiyeh, northwestern province of West Azarbaijan, next week.
The competition is held between May and July 2019 and the final round will take place in the Credit Union 1 Arena, Chicago, United States.
This is the first edition of the World League or the Nations League to have the Final Round hosted in North America.