Both teams are so far undefeated in the tournament.
Northern Ireland who are ranked 12th in the world have done it relatively easy with wins over Botswana, Singapore Invitational and Chinese Taipei.
The 16th placed Pepes on the other hand have also registered wins over the same teams but by closer margins.
The match will get underway at 5pm (7pm PNG time) at the OCBC Arena.
PNG Netball President, Julienne Leka Maliaki said she is confident the Pepes can cause an upset.