2022–23 Royale Union Saint-Gilloise season

The 2022–23 season was the 125th in the history of Royale Union Saint-Gilloise and their second consecutive season in the top flight. The club participated in the Belgian Pro League, Belgian Cup,UEFA Champions League and UEFA Europa League.

Matches
The league fixtures were announced on 22 June 2022.

Play-offs I
Points obtained during the regular season were halved (and rounded up) before the start of the playoff. Genk and Union SG, therefore, started on 38 points, Antwerp on 36, and Club Brugge on 30. In case of ties between some of the teams, their relative order would be based on the following list: Antwerp (points not rounded up), Genk (regular season ranked 1), Union SG (regular season ranked 2), Club Brugge (regular season ranked 4).

Third qualifying round
The draw for the third qualifying round was held on 18 July 2022.

Group stage
The draw for the group stage was held on 26 August 2022.

Round of 16
The draw for the round of 16 was held on 24 February 2023.

Quarter-finals
The draw for the quarter-finals was held on 17 March 2023.

Squad appearances and goals

 * Last updated on 4 June 2023

! colspan=14 style=background:#dcdcdc; text-align:center|Goalkeepers

! colspan=14 style=background:#dcdcdc; text-align:center|Defenders

! colspan=14 style=background:#dcdcdc; text-align:center|Midfielders

! colspan=14 style=background:#dcdcdc; text-align:center|Forwards

! colspan=14 style=background:#dcdcdc; text-align:center|Players who have made an appearance this season but have left the club


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