2017 in South Korean football
This article shows the 2017 season of South Korean football. K League. Promotion-relegation playoffs. The promotion-relegation playoffs were held between the winners of the 2017 K League Challenge playoffs and the 11th-placed club of the 2017 K League Classic. The winner on aggregate score after both matches earned entry into the 2018 K League 1. "1–1 on aggregate. Sangju Sangmu won 5–4 on penalties and therefore both clubs remain in their respective leagues."