(Click on the column title to sort by that column)
| # | Catholics | Population | Percent Catholic | Diocese | Year | Source |
|---|---|---|---|---|---|---|
| 1 | 147,350 | 180,000 | 81.86% | Bougainville | 2004 | ap2005 |
| 2 | 67,933 | 83,733 | 81.13% | Bereina | 2004 | ap2005 |
| 3 | 72,000 | 95,500 | 75.39% | Aitape | 2004 | ap2005 |
| 4 | 195,950 | 295,700 | 66.27% | Wewak | 2004 | ap2005 |
| 5 | 120,000 | 201,639 | 59.51% | Kimbe | 2004 | ap2005 |
| 6 | 131,500 | 235,600 | 55.81% | Rabaul (Archdiocese) | 2004 | ap2005 |
| 7 | 142,000 | 285,154 | 49.80% | Madang (Archdiocese) | 2004 | ap2005 |
| 8 | 79,000 | 180,000 | 43.89% | Kavieng | 2004 | ap2005 |
| 9 | 142,725 | 386,408 | 36.94% | Mount Hagen (Archdiocese) | 2004 | ap2005 |
| 10 | 102,208 | 280,000 | 36.50% | Kundiawa | 2004 | ap2005 |
| 11 | 183,889 | 512,386 | 35.89% | Port Moresby (Archdiocese) | 2004 | ap2005 |
| 12 | 32,000 | 95,000 | 33.68% | Vanimo | 2004 | ap2005 |
| 13 | 69,000 | 260,000 | 26.54% | Wabag | 2004 | ap2005 |
| 14 | 37,109 | 153,247 | 24.22% | Daru-Kiunga | 2004 | ap2005 |
| 15 | 22,130 | 106,800 | 20.72% | Kerema | 2004 | ap2005 |
| 16 | 34,462 | 217,000 | 15.88% | Alotau-Sideia | 2004 | ap2005 |
| 17 | 71,832 | 546,400 | 13.15% | Mendi | 2004 | ap2005 |
| 18 | 30,000 | 430,000 | 6.98% | Lae | 2004 | ap2005 |
| 19 | 13,500 | 429,480 | 3.14% | Goroka | 2004 | ap2005 |
|