ERO was directed to slash 6.5 percent of its spending amid wider public sector cuts, and has proposed to disestablish 25 roles and create 12 new ones, it said on Friday.
The roles being disestablished include review officers who assess how well school and early childhood centres are educating children, PSA assistant secretary Fleur Fitzsimons said.
"We all know that the education system is facing a huge challenge to ensure students are achieving at the level they should be, so why cut the very agency charged with driving up quality?"
The government was sending mixed messages, she believed.
"On the one hand it says lifting achievement is its number one education priority, yet it has forced the Ministry of Education to shed 755 jobs, cut 35 roles at the New Zealand Qualification Authority and 28 at the Tertiary Education Commission. And now ERO.
"This just doesn't add up."
The office employs about 250 staff, its website said.
ERO has been approached for comment.
Redundancies at Environment Ministry
`Meanwhile, 44 staff have accepted offers of voluntary redundancy at the Ministry for the Environment.
The ministry called for voluntary redundancies last month to help meet its target of reducing costs by 7.5 percent - and more were on the cards.
"There will be a second invitation to express an interest in voluntary redundancy following the release of a formal change proposal - likely in early June," a spokesperson said today.
"We won't know how many other staff may be affected until the government finalises Budget 2024 on 30 May. We will then seek feedback from staff on a proposal to reduce the organisation in size."
