Head to Head
| England Development League 2 | 2023/02/21 12:00 | Cardiff U21 v Millwall U21 | W | 4-2 |
| England Development League 2 | 2022/10/31 14:00 | Millwall U21 v Cardiff U21 | L | 5-0 |
Home History
| Wales League Cup | 2023/09/19 18:30 | Swansea U21 v Cardiff U21 | D | 1-1 |
| England Development League 2 | 2023/09/12 12:00 | Sheff Utd U21 v Cardiff U21 | L | 6-2 |
| England Development League 2 | 2023/09/01 13:00 | Cardiff U21 v Barnsley U21 | W | 2-1 |
| England Development League 2 | 2023/08/26 10:00 | Burnley U21 v Cardiff U21 | D | 2-2 |
| England Development League 2 | 2023/08/22 11:00 | Cardiff U21 v Sheffield Wed U21 | D | 3-3 |
| England Development League 2 | 2023/08/15 12:00 | Fleetwood Town U21 v Cardiff U21 | L | 4-1 |
| Wales League Cup | 2023/08/06 13:30 | Haverfordwest County v Cardiff U21 | W | 0-4 |
| Wales League Cup | 2023/07/21 18:30 | Cambrian United v Cardiff U21 | W | 5-6 |
Away History
| England Development League 2 | 2023/09/11 13:00 | Birmingham U21 v Millwall U21 | D | 3-3 |
| England Development League 2 | 2023/09/04 13:00 | Millwall U21 v Crewe U21 | W | 2-0 |
| England Development League 2 | 2023/08/30 12:00 | Hull U21 v Millwall U21 | W | 2-3 |
| England Development League 2 | 2023/08/21 13:00 | Millwall U21 v Burnley U21 | W | 3-1 |
| England Development League 2 | 2023/08/15 13:00 | Sheffield Wed U21 v Millwall U21 | D | 2-2 |
| England Development League 2 | 2023/05/22 18:00 | Millwall U21 v Sheff Utd U21 | D | 1-1 |
| England Development League 2 | 2023/05/15 13:00 | Millwall U21 v Hull U21 | D | 3-3 |
| England Development League 2 | 2023/05/05 11:30 | Millwall U21 v Sheffield Wed U21 | W | 3-0 |