| 1. Round | 12/09/2020 | Walsall FC | - | Grimsby Town | 1:0 | ||||
| 5. Round | 10/10/2020 | Bolton Wanderers | - | Grimsby Town | 0:0 | ||||
| 13. Round | 21/11/2020 | Tranmere Rovers | - | Grimsby Town | 5:0 | ||||
| 14. Round | 24/11/2020 | Crawley Town | - | Grimsby Town | 1:2 | ||||
| 15. Round | 01/12/2020 | Grimsby Town | - | Exeter City | 1:4 | ||||
| 16. Round | 05/12/2020 | Colchester United | - | Grimsby Town | 2:1 | ||||
| 24. Round | 16/01/2021 | Grimsby Town | - | Southend United | 0:0 | ||||
| 30. Round | 27/04/2021 | Exeter City | - | Grimsby Town | 3:2 | ||||
| 45. Round | 01/05/2021 | Grimsby Town | - | Port Vale FC | 1:0 | ||||
| 46. Round | 08/05/2021 | Cambridge United | - | Grimsby Town | 3:0 |
England