Iran have moved up to 22nd place in the world, while Japan dropped to 26th.
Iran replaced Japan thanks to victories against Syria and Iraq in Group A of the 2022 World Cup qualification Round 3.
Japan’s defeat to Oman in Group B saw the Blue Samurai drop to second in the FIFA World Ranking.
Australia remain third in the ranking.
Belgium remain first, followed by Brazil and England.
Belgium have been top of the rankings since 2018, despite failing to win an international tournament in that period.
The next FIFA World Ranking will be published on Oct. 21.