Round 4
| Date | Winner | Score | Loser | Score | Venue |
|---|---|---|---|---|---|
| 3/05/78 | Easts | 16 | Wests | 10 | Leichhardt Oval |
| 24/05/78 | Auckland | 39 | Riverina | 3 | Leichhardt Oval |
| 7/06/78 | Parramatta | 28 | Brisbane Wests | 0 | Leichhardt Oval |
| 14/06/78 | Cronulla | 15 | Monaro | 8 | Queanbeyan |
| 14/06/78 | Illawarra | 19 | Balmain | 10 | Leichhardt Oval |
| 27/06/78 | St George | 35 | Newtown | 11 | Leichhardt Oval |
| 4/07/78 | Manly | 11 | South Sydney | 9 | Lang Park |
| 5/07/78 | Brisbane Easts | 27 | North Sydney | 6 | Lang Park |
Read more about this topic: 1978 Amco Cup