| 1. Round | 22/08/1998 | Apollon Smyrnis | - | Olympiakos Piraeus | 2:5 |  |
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| 2. Round | 29/08/1998 | Olympiakos Piraeus | - | Panelefsiniakos Elefsinas | 1:1 | ||||
| 3. Round | 12/09/1998 | Veria FC | - | Olympiakos Piraeus | 0:3 | |
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| 5. Round | 25/09/1998 | Paniliakos Pyrgos | - | Olympiakos Piraeus | 1:0 | ||||
| 7. Round | 24/10/1998 | Ethnikos Asteras | - | Olympiakos Piraeus | 1:3 | ||||
| 8. Round | 30/10/1998 | PAOK Saloniki | - | Olympiakos Piraeus | abor. | |
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| 9. Round | 08/11/1998 | Olympiakos Piraeus | - | Ionikos Nikea | 2:0 | ||||
| 10. Round | 21/11/1998 | Aris Saloniki | - | Olympiakos Piraeus | 1:0 | ||||
| 13. Round | 13/12/1998 | Olympiakos Piraeus | - | Ethnikos Piraeus | 2:0 | ||||
| 15. Round | 15/01/1999 | Olympiakos Piraeus | - | Skoda Xanthi | 3:1 | ||||
| 17. Round | 29/01/1999 | AEK Athen | - | Olympiakos Piraeus | 2:0 | ||||
| 23. Round | 12/03/1999 | AO Proodeftiki | - | Olympiakos Piraeus | 0:1 | ||||
| 28. Round | 01/05/1999 | AO Kavala | - | Olympiakos Piraeus | 0:2 | ||||
| 29. Round | 08/05/1999 | Olympiakos Piraeus | - | Panathinaikos | 0:0 | ||||
| 30. Round | 11/05/1999 | Ethnikos Piraeus | - | Olympiakos Piraeus | 0:3 |
Ghana