The 2020–21 Iraq Division One was the 47th season of the Iraq Division One, the second tier of the Iraqi football league system since its establishment in 1974. The number of clubs in the league have changed throughout history due to several factors, most recently in this season when the number of clubs increased from 12 to 28 in total. The top team from each group is directly promoted to the Premier League, while a third club can be promoted through play-offs, on the other hand, two clubs from each group are directly relegated to the Division Two.