The 2013 K League Challenge was the first season of the K League 2, the second-highest division in the South Korean football league system. Its schedule was announced on 30 January 2013, and it began on 16 March.
Relegated from K League
Promoted from Korea National League
Promoted from Challengers League
Promoted from R League
Newly formed
<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 including a least one player from the AFC country.
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Sangju Sangmu won 4âÂÂ2 on aggregate and were promoted to the K League Classic, while Gangwon FC were relegated to the K League Challenge.
Attendants who entered with free ticket were not counted. Korean Police played all matches at opponents' stadiums.
The 2013 K League Awards was held on 3 December 2013.