| Club: | Rayo Vallecano |
| Season: | 2021–22 |
| Ownertitle: | Owner |
| Owner: | Raúl Martín Presa |
| Chrtitle: | President |
| Chairman: | Raúl Martín Presa |
| Mgrtitle: | Head coach |
| Manager: | Andoni Iraola |
| Stadium: | Campo de Fútbol de Vallecas |
| League: | La Liga |
| League Result: | 12th |
| Cup1: | Copa del Rey |
| Cup1 Result: | Semi-finals |
| League Topscorer: | Sergi Guardiola (8) |
| Season Topscorer: | Sergi Guardiola (10) |
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| Prevseason: | 2020–21 |
| Nextseason: | 2022–23 |
The 2021–22 season was the 98th season in the existence of Rayo Vallecano and the club's first season back in the top flight of Spanish football. In addition to the domestic league, Rayo Vallecano participated in this season's edition of the Copa del Rey.
See main article: Rayo Vallecano B.
| Date | Player | From | Type | Fee | Ref |
|---|---|---|---|---|---|
| 30 June 2021 | align=center colspan=2 | Loan return | [2] | ||
| 13 July 2021 | Transfer | Undisclosed | [3] | ||
| 14 July 2021 | Transfer | Free | [4] | ||
| 4 September 2021 | Transfer | Free | |||
| Date | Player | To | Type | Fee | Ref |
|---|---|---|---|---|---|
| 30 June 2021 | align=center colspan=2 | Loan return | [5] | ||
| 30 June 2021 | align=center colspan=2 | Loan return | [6] | ||
| 30 June 2021 | align=center colspan=2 | Loan return | [7] | ||
See main article: 2021–22 La Liga.
The league fixtures were announced on 30 June 2021.[8] [9]
See main article: 2021–22 Copa del Rey.
|-! 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|-|}
| Rank | Player | La Liga | Copa del Rey | Total | |
|---|---|---|---|---|---|
| 1 |  Sergi Guardiola | 8 | 2 | 10 | |
| 2 | Álvaro García | 7 | 1 | 8 | |
| 3 |  Radamel Falcao | 6 | 0 | 6 | |
| 4 |  Óscar Trejo | 3 | 1 | 4 | |
| 5 |  Randy Nteka | 3 | 0 | 3 | |
 Pathé Ciss | 2 | 1 | 3 | ||
| Total | 29 | 5 | 34 | ||