RNZ reports SOE portfolios in eight Pacific countries examined contribute only 1.8% to 12% of gross domestic product, despite having very large asset bases, ongoing government cash transfers, and monopoly market positions.
The ADB said productivity levels of the SOEs were also well below that found in developed countries.
But the Bank noted some successes in pursuing commercially-oriented reforms.
It said that over the past 14 years Solomon Islands has improved significantly, with Tonga also doing better.