| Club: | Willem II |
| Season: | 2020–21 |
| Chrtitle: | Chairman |
| Chairman: | Jack Buckens |
| Mgrtitle: | Manager |
| Manager: | Adrie Koster |
| Stadium: | Koning Willem II Stadion |
| League: | Eredivisie |
| League Result: | 14th |
| Cup1: | KNVB Cup |
| Cup1 Result: | Second round |
| Cup2: | UEFA Europa League |
| League Topscorer: | Vangelis Pavlidis (10) |
| Season Topscorer: | Vangelis Pavlidis (12) |
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| Prevseason: | 2019–20 |
| Nextseason: | 2021–22 |
The 2020–21 Willem II season was the club's 125th season in existence and the club's 7th consecutive season in the top flight of Dutch football. In addition to the domestic league, Willem II participated in this season's editions of the KNVB Cup and the UEFA Europa League. The season covered the period from 1 July 2020 to 30 June 2021.
| scope=col | Player | Transferred from | scope=col; style="width: 65px;" | Fee | scope=col | Date | scope=col | Source | ||
|---|---|---|---|---|---|---|---|---|---|---|
| 15 | TBD |
| scope=col | Player | Transferred to | scope=col; style="width: 65px;" | Fee | scope=col | Date | scope=col | Source | ||
|---|---|---|---|---|---|---|---|---|---|---|
| 15 | TBD |
See main article: 2020–21 Eredivisie.
The league fixtures were announced on 24 July 2020.[1]
See main article: 2020–21 KNVB Cup.
See main article: 2020–21 UEFA Europa League.