| 5. Round | 12/08/2017 | NK Inter Zaprešić | - | NK Istra 1961 | 2:2 | ||||
| 6. Round | 18/08/2017 | NK Istra 1961 | - | HNK Cibalia | 0:1 | ||||
| 7. Round | 27/08/2017 | Hajduk Split | - | NK Istra 1961 | 2:0 |  |
|||
| 8. Round | 08/09/2017 | NK Istra 1961 | - | Slaven Belupo | 1:0 |  |
|
||
| 9. Round | 17/09/2017 | NK Rudeš | - | NK Istra 1961 | 1:0 | ||||
| 10. Round | 24/09/2017 | NK Istra 1961 | - | Dinamo Zagreb | 0:0 | ||||
| 11. Round | 01/10/2017 | NK Osijek | - | NK Istra 1961 | 2:1 | |
|||
| 13. Round | 22/10/2017 | Lokomotiva Zagreb | - | NK Istra 1961 | 1:0 | ||||
| 14. Round | 30/10/2017 | NK Istra 1961 | - | NK Inter Zaprešić | 1:1 | ||||
| 17. Round | 25/11/2017 | Slaven Belupo | - | NK Istra 1961 | 2:0 | ||||
| 18. Round | 04/12/2017 | NK Istra 1961 | - | NK Rudeš | 2:1 | ||||
| 19. Round | 09/12/2017 | Dinamo Zagreb | - | NK Istra 1961 | 5:1 | ||||
| 20. Round | 16/12/2017 | NK Istra 1961 | - | NK Osijek | 1:1 |  |
Croatia