Ulsan Hyundai Football Club (K League 1): every transfer in and out, fees paid and earned, squad market value, €8.9m spent and €11m earned.
| Date | Player | From | To | Fee |
|---|---|---|---|---|
| 2026-08-03 | Yool Heo | Ulsan HD | Gimcheon Sangmu | Loan |
| 2026-02-20 | Woo-jin Park | Suwon Bluewings | Ulsan HD | — |
| 2026-02-20 | Min-hyuk Lee | Suwon Bluewings | Ulsan HD | — |
| 2026-02-14 | Benji Michel | HJK Helsinki | Ulsan HD | Free |
| 2026-02-12 | Jae-sang Jeong | Daegu FC | Ulsan HD | — |
| 2026-02-11 | Chung-yong Lee | Ulsan HD | Incheon Utd. | — |
| 2026-01-16 | Won-sang Um | Ulsan HD | Daejeon Hana C. | Free |
| 2026-01-16 | Pedrinho | Seoul E-Land | Ulsan HD | — |
| 2026-01-16 | Min-seo Jo | Dankook Univ | Ulsan HD | Free |
| 2026-01-16 | Ju-ho Choi | Ulsan HD U18 | Ulsan HD | — |
| 2026-01-16 | Jae-seok Hong | Ulsan HD | FC Anyang | — |
| 2026-01-16 | Gustav Ludwigson | Ulsan HD | Daejeon Hana C. | Free |
| 2025-12-15 | Min-seo Park | Ulsan HD | Gimcheon Sangmu | Loan |
| 2025-12-15 | Jae-seok Yoon | Ulsan HD | Gimcheon Sangmu | Loan |
| 2025-07-18 | Marcão | Al-Ahli | Ulsan HD | Free |
| 2025-07-09 | Seung-hyun Jung | Al-Wasl | Ulsan HD | Free |
| 2025-07-06 | Yago Cariello | Ulsan HD | ZJ FC | Loan |
| 2025-06-13 | Sang-min Sim | Ulsan HD | Gwangju FC | Loan |
| 2025-06-10 | Si-young Jang | Ulsan HD | Bucheon FC | Loan |
| 2025-06-05 | Milosz Trojak | Korona Kielce | Ulsan HD | Free |