2nd Division

Iranian football's 2nd division (Persian: ليگ دسته دوم ایران) is the third-highest football division overall in the Iranian football league system. Before 2001, the 2nd division league was the second-highest division in the national football league system. However, it was changed to third-highest division when Iran's football structure officially became professional.

The league consists of two, 14-team groups who play each other twice in a home and away format. The first- and second-placed teams in each group are automatically promoted to the Azadegan League. The bottom two teams in both groups are automatically relegated to the 3rd division.

If teams in the promotion or relegation spots are tied in terms of points, a home and away series will be played. The team with the best aggregate score will either avoid relegation or win promotion.

Sometimes these rules are not followed exactly. For example in the 2005–06 season, Deihim Ahvaz should have been relegated, but Nozhan Mazandaran despite finishing ahead of Deihim, were relegated instead because of the club's poor financial situation. Additionally the number of teams in each group was increased from twelve to fourteen this season.