| 1. Jornada | 28.02.2021 | Mito HollyHock | - | RB Omiya Ardija | 1:2 | ||||
| 2. Jornada | 06.03.2021 | RB Omiya Ardija | - | Ventforet Kofu | 0:2 | ||||
| 4. Jornada | 21.03.2021 | SC Sagamihara | - | RB Omiya Ardija | 2:1 |  |
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| 3. Jornada | 24.03.2021 | RB Omiya Ardija | - | Kyoto Sanga FC | 1:2 | ||||
| 8. Jornada | 17.04.2021 | RB Omiya Ardija | - | Ehime FC | 0:1 | ||||
| 9. Jornada | 21.04.2021 | Júbilo Iwata | - | RB Omiya Ardija | 3:2 | ||||
| 10. Jornada | 25.04.2021 | RB Omiya Ardija | - | FC Machida Zelvia | 0:1 | ||||
| 12. Jornada | 05.05.2021 | RB Omiya Ardija | - | Albirex Niigata | 2:3 | ||||
| 18. Jornada | 13.06.2021 | RB Omiya Ardija | - | Tochigi SC | 1:1 | ||||
| 22. Jornada | 11.07.2021 | V-Varen Nagasaki | - | RB Omiya Ardija | 1:1 | ||||
| 23. Jornada | 18.07.2021 | RB Omiya Ardija | - | FC Ryūkyū | 2:2 | ||||
| 24. Jornada | 09.08.2021 | Albirex Niigata | - | RB Omiya Ardija | 2:2 | ||||
| 29. Jornada | 12.09.2021 | Ehime FC | - | RB Omiya Ardija | 3:3 | ||||
| 30. Jornada | 18.09.2021 | Ventforet Kofu | - | RB Omiya Ardija | 1:0 | ||||
| 31. Jornada | 25.09.2021 | RB Omiya Ardija | - | SC Sagamihara | 1:0 | ||||
| 32. Jornada | 03.10.2021 | Tochigi SC | - | RB Omiya Ardija | 1:3 | ||||
| 33. Jornada | 09.10.2021 | RB Omiya Ardija | - | Zweigen Kanazawa | 2:2 |
Japón