An-Nur childcare centres manager Dr Maysoon Salama said the findings did not surprise her.
Many parents using their centres in Christchurch and Dunedin were struggling to pay fees even though at $5.50 per hour they were among the cheapest in the country and had not risen since 2011.
Salama said many parents compromised on childcare with some shift workers looking after their children during what should be their sleep time.
Migrant workers without permanent residency and foreign students with children under the age of three were particularly affected by high childcare costs because they were not eligible for Work and Income support.
Ministry of Education head of evidence, data and knowledge, Craig Jones, rejected the report's findings.
It over-estimated the time children spent in childcare in New Zealand (which assumed two children in full-time childcare for the entire year) and overlooked the first 20-hours of childcare subsidy available to the parents of three to five year olds.
"Per-child early childhood education funding in New Zealand is among the highest in the OECD. Funding for early children education has risen every year for the last 10 years."
Early Childhood Council chief executive Peter Reynolds had no doubt that the cost of childcare here was rising.
"The Government has been cutting childcare subsidies by stealth since 2010."
However, Reynolds said the report did not paint an accurate picture of childcare in New Zealand because of its broad assumptions.
Childcare costs here were high but not as bad as what the study had reported.
University of Canterbury early childhood education researcher Parisa Soleimani Tadi said cost barriers to attending childcare centres could delay children's development "especially in early learning areas of literacy and numeracy".
The OECD report, Society At A Glance 2016, states high childcare costs are likely to affect mothers the most.
"It may not be financially worthwhile for both partners to work, and it is usually the mother who stays at home," the report says.
The study is part of OECD biennial report which provides an overview of social indicators in 35 OECD member countries. Other countries included in the report are Brazil, China, India, Indonesia, Russia, South Africa, Argentina and Saudi Arabia.
Case Study
Young immigrant parents Behnam and Negar Boddouhi say childcare has been one of their biggest challenge in starting a new life in Christchurch.
The Boddouhis moved to New Zealand with their now 3-year-old daughter in March last year.
With no family to act as a support network and with pressures of full-time study and work, the Boddouhi family said they had no choice but to put their daughter in full-time childcare.
Quantity Surveyor, Boddouhi, 32, said the cost of childcare for them reduced when Diba turned 3.
"We used to pay $222 per week for childcare which was a lot," he said.
Their daughter spends 42 hours per week in childcare for which the family now receives a 20-hour subsidy from the Government, reducing their childcare costs to $144.76 per week.
The Boddouhis said their biggest challenge was during school holidays when their childcare centre was closed.
"That's really costly for us because one of us has to stay at home to look after Diba."
Behnam Boddouhi said anything the Government could do to ease the cost of childcare would be "hugely welcomed" by his family.
