The 2015 K League Challenge was the third season of the K League 2, the second-highest division in the South Korean football league system. Champions and winners of promotion playoffs could be promoted to the K League Classic.
Relegated from K League Classic
Promoted to K League Classic
Newly joined
<small>Note: Flags indicate national team as has been defined under FIFA eligibility rules. Players may hold more than one non-FIFA nationality.</small>
Restricting the number of foreign players strictly to four per team, including a slot for a player from AFC countries. A team could use four foreign players on the field each game.
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When the first round and semi-final match were finished as draws, their winners were decided on the regular season rankings without extra time and the penalty shoot-out.
The promotion-relegation playoffs were held between the winners of the 2015 K League Challenge playoffs and the 11th-placed club of the 2015 K League Classic. The winners on aggregate score after both matches earned entry into the 2016 K League Classic.
Suwon FC won 3âÂÂ0 on aggregate and were promoted to the K League Classic, while Busan IPark were relegated to the K League Challenge.
Attendants who entered with free ticket were not counted.
The 2015 K League Awards was held on 1 December 2015.