Zugänge
| Zeitraum | Name | Pos. | Mannschaft | Team | ||
|---|---|---|---|---|---|---|
| 07/2021 |  | Kyu-hyun Park | AB | | Werder Bremen II | Werder II |
| 06/2021 | | Myung-jae Lee | AB | | Gimcheon Sangmu | Gimcheon Sangmu |
| 06/2021 | | Yong-woo Park | MF | | Gimcheon Sangmu | Gimcheon Sangmu |
| 06/2021 | | Se-hun Oh | ST | | Gimcheon Sangmu | Gimcheon Sangmu |
| 02/2021 | | Dong-jun Lee | MF | | Busan IPark | Busan IPark |
| 01/2021 | | Lukas Hinterseer | ST | | Hamburger SV | Hamburger SV |
| 01/2021 | | Ho Lee | MF | | Ayutthaya FC | Ayutthaya FC |
| 01/2021 | | Ji-hyeon Kim | ST | | Gangwon FC | Gangwon FC |
| 01/2021 | | Dong-hee Lee | AB | | Honam University | Honam University |
| 01/2021 | | Dong-hyeok Kang | MF | | Ulsan University | Ulsan University |
| 01/2021 | | Hyung-min Shin | MF | | Jeonbuk FC | Jeonbuk |
| 01/2021 | | Jun Choi | AB | | Gyeongnam FC | Gyeongnam FC |
| 01/2021 | | Tae-hyeon Kim | AB | | Seoul E-Land FC | Seoul E-Land FC |
| 01/2021 | | Young-sun Yun | AB | | FC Seoul | FC Seoul |
| 01/2021 | | Valeri Qazaishvili | MF | | San Jose Earthquakes | Earthquakes |
| 01/2021 | | Yun-gu Kang | ST | |||
| 01/2021 | | Min-jun Kim | ST | | Ulsan University | Ulsan University |
| 01/2021 | | Hyeong-kyeong Lee | ST | | Sungkyunkwan University | Sungkyunkwan University |
| 01/2021 | | Myung-bo Hong | TR | |||
| 01/2021 | | Sang-rok Kim | CO-TR |
Abgänge
| Zeitraum | Name | Pos. | Mannschaft | Team | ||
|---|---|---|---|---|---|---|
| 02/2021 | | Júnior Negrão | ST | | Changchun Yatai | Changchun Yatai |
| 02/2021 | | Sang-heon Lee | ST | | Busan IPark | Busan IPark |
| 02/2021 | | Jun Choi | AB | | Busan IPark | Busan IPark |
| 02/2021 | | Hoon-sung Jung | MF | | Busan IPark | Busan IPark |
| 02/2021 | | Bjørn Johnsen | ST | | CF Montréal | Montréal |
| 01/2021 | | Joo-ho Park | AB | | Suwon FC | Suwon FC |
| 01/2021 | | Keun-ho Lee | ST | | Daegu FC | Daegu FC |
| 01/2021 | | Jeong-in Park | ST | | Busan IPark | Busan IPark |
| 01/2021 | | Dong-hwan Min | TW | | Suwon FC | Suwon FC |
| 01/2021 | | Jin-ho Shin | MF | | Pohang Steelers | Pohang Steelers |
| 01/2021 | | Min-deok Kim | AB | | Daejeon Hana Citizen | Daejeon |
| 01/2021 | | Jae-won Jang | MF | | Ulsan Citizen FC | Ulsan Citizen FC |
| 01/2021 | | Gi-woon Lee | ST | | Ulsan Citizen FC | Ulsan Citizen FC |
| 01/2021 | | Dong-ho Jeong | AB | | Suwon FC | Suwon FC |
| 01/2021 | | Young-sun Yun | AB | | Suwon FC | Suwon FC |
| 01/2021 | | Ha-bin Park | MF | | Bucheon FC 1995 | Bucheon FC 1995 |
