The 2025 season is Ulsan HD FC's 42nd season in the K League 1, and the first season under the new name after rebranding from Ulsan Hyundai FC. Over the course of the season, the club participated in the 2025 K League 1, the 2024 Korean FA Cup, the 2024–25 AFC Champions League Elite, the 2025–26 AFC Champions League Elite after being the 2024 K League 1 champion, and the FIFA Club World Cup.
Transfers.
Pre-season.
In.
Transfers in
Returned from loan
Rumors in
Out.
Transfers out
Loaned out
Rumored out
Mid-season.
In.
Transfers in
Returned from loan
Out.
Transfers out
Loaned out
Competitions.
K League 1.
Matches.
As usual, the league season is played over 38 matches. After 33 league matches between the 12 participating teams, the teams are split into the final round (top 6 teams) and relegation round (bottom 6 teams).