| Club: | Fortuna Sittard |
| Season: | 2020–21 |
| Chrtitle: | Chairman |
| Chairman: | Özgür Işıtan Gün |
| Mgrtitle: | Manager |
| Manager: | Kevin Hofland |
| Stadium: | Fortuna Sittard Stadion |
| League: | Eredivisie |
| League Result: | 11th |
| Cup1: | KNVB Cup |
| Cup1 Result: | Round of 16 |
| League Topscorer: | Zian Flemming (12) |
| Season Topscorer: | Zian Flemming (15) |
| Pattern La1: | _fortunasittard2021h |
| Pattern B1: | _fortunasittard2021h |
| Pattern Ra1: | _fortunasittard2021h |
| Leftarm1: | FFFF00 |
| Body1: | FFFF00 |
| Rightarm1: | FFFF00 |
| Shorts1: | 00684B |
| Socks1: | FFFF00 |
| Pattern La2: | _fortunasittard2021a |
| Pattern B2: | _fortunasittard2021a |
| Pattern Ra2: | _fortunasittard2021a |
| Leftarm2: | 182E63 |
| Body2: | 182E63 |
| Rightarm2: | 182E63 |
| Shorts2: | F37029 |
| Socks2: | F37029 |
| Pattern La3: | _fortunasittard1920a |
| Pattern B3: | _fortunasittard1920a |
| Pattern Ra3: | _fortunasittard1920a |
| Leftarm3: | 006400 |
| Body3: | 006400 |
| Rightarm3: | 006400 |
| Shorts3: | ffffff |
| Socks3: | ffffff |
| Prevseason: | 2019–20 |
| Nextseason: | 2021–22 |
The 2020–21 season was the 53rd season in existence of Fortuna Sittard and the club's third consecutive season in the top flight of Dutch football. In addition to the domestic league, Fortuna Sittard participated in this season's edition of the KNVB Cup. The season covered the period from 1 July 2020 to 30 June 2021.
See main article: 2020–21 Eredivisie.
The league fixtures were announced on 24 July 2020.[1]
See main article: 2020–21 KNVB Cup.