Unicef New Zealand chief executive Michelle Sharp said low-income families were missing out.
"That basically means that an average couple in New Zealand of income earners would have to spend 37 per cent of their salaries to put two children to full-time childcare, which is a huge amount."
The report pointed out that Ireland, New Zealand and Switzerland had the least affordable childcare for the middle-class population.
Children's Commissioner Judge Andrew Becroft called the report on childcare by Unicef: "fascinating but troubling".
He was reassured that the quality of care was high, but was surprised by some information.
"I hadn't realised we were so far down the table in partner support, and I didn't realise that we were so relatively costly, and that's a problem for me."
Becroft believed increasing the family tax credit would help make childcare more affordable.
In New Zealand, mothers are entitled to 26 weeks paid parental leave, and partners to two weeks of unpaid leave.
Victoria University Professor of Early Childhood Studies Carmen Dalli said the report showed the country was doing some things well, "it's a good reminder that the work is not yet done".
"We should not underplay the finding about quality: because it's the quality of services that matters for children's development.
"This government has a policy focus on wellbeing; improving affordability and longer parental leave would support wellbeing for children as well as for families and all of society."
Top 10 countries for childcare according to Unicef
1. Luxembourg
2. Iceland
3. Sweden
4. Norway
5. Germany
6. Portugal
7. Latvia
8. Denmark
9. South Korea
10. Estonia