South Korean football league system

The South Korean football league system contains two professional leagues, two semi-professional leagues, and various amateur leagues for Korean football clubs.

The highest level of football in South Korea is the K League 1, which was founded in 1983. K League 2 was founded in 2013 and is currently a second division. Below the level of the professional leagues are the semi-professional K3 League, which was founded in 2007 and refounded in 2020, and the K4 League, which was founded in 2020, and serve as the third division and fourth division, respectively.

There was no avenue for progression between any of the leagues until 2012, when the K League 2 was founded.

The highest level of women's football in South Korea is the WK League, which was founded in 2009.

System by period
Korean National Semi-Professional Football League was a semi-professional football league between corporate teams in South Korea from 1964 to 2002. In 1983, with the establishment of K League which is a professional league, the Semi-professional League became the second tier and remained so until it was replaced by the Korea National League in 2003. The third tier K3 League was founded as an amateur league in 2007, and became the fourth tier after K League 2, the second division of the professional league, was founded in 2013. In 2017, the K3 League was divided into two divisions, the K3 League Advanced and the K3 League Basic. They were relaunched as semi-professional leagues with new names, K3 League and K4 League, in 2020. The National League was merged into the K3 League.

Promotion and relegation takes place within each of three classes (professional, semi-professional and amateur) but at present there is no promotion and relegation between classes. The KFA has announced plans to unify the league system with promotion and relegation between all seven leagues starting from the 2027 season.

Current system
Outside this league structure, there are university, reserve and youth level competitions. University clubs' U-League and reserve teams' R League are operating independently from the league system. Relegation from K League 2 to K3 League and K4 League to K5 League from 2027 have been introduced.

Domestic cups
All K League, K3 League and K4 League sides qualify for the Korean FA Cup tournament. The top eleven sides from the K5 League gained qualification to the 2020 season's FA Cup tournament. The Korean League Cup competition was open to K League teams only, whilst sides from the National League could compete in the National League Championship, but both were abolished.

Continental competition
At present, four South Korean sides qualify automatically for the AFC Champions League. Three top teams from K League 1 automatically gains entry to the AFC Champions League. The Korean FA Cup winners also qualify for the AFC Champions League only. However, if the champions of Korean FA Cup are not members of K League, the fourth placed team of the K League 1 receive the entry spot.