The 2021–22 Iraq Division One was the 48th 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 varied throughout history for various reasons; in this season the number of clubs has been reduced from 28 teams to 24. The top two teams are directly promoted to the Iraqi Premier League, while the bottom 4 teams in each group are directly relegated to the Iraq Division Two. The season started on 12 October 2021 and ended 19 April 2022, while the summer transfer window began on August 1 and ended on midnight on September 19.