The K3 League had an
exhibition season held in two stages with ten teams in 2007. The winners of both stages and the best two clubs in the overall standings qualified for the championship playoffs and the
2008 Korean FA Cup.
Seoul United became inaugural champions after winning the championship playoffs. After the league was officially launched in 2008, the number of participating clubs was increased to 18 until the
2010 season, while new clubs registered in the league or some of the existing clubs were dissolved due to financial problems.
Seoul Pabal, which engaged in match-fixing scandal during the
2008 season, was also dissolved at that time. It was renamed the
Challengers League in 2011 and the
K3 Challengers League in 2014, but used original name again since 2015 after being criticised for being confused with a youth league of
K League clubs (which had the same name) and the
K League Challenge. In 2017, it introduced a system of promotion and relegation, and was divided into the first division
K3 League Advanced and the second division the
K3 League Basic. After the
2019 season, amateur level K3 League was revamped as a semi-professional league with the same name. The
Korea National League and the K3 League Advanced were absorbed into the third division and were rebranded as the new K3 League. ==Competition format==