The Child Wellbeing Unit, to be funded by Oranga Tamariki, will develop strategy to improve child wellbeing. It will seek public views on policy priorities for the strategy later this year.
"This Coalition Government is committed to genuinely tackling child poverty so that New Zealand becomes the best place in the world to be a child," said Prime Minister and Minister for Child Poverty Reduction Jacinda Ardern.
An extra $25.7m for Statistics New Zealand over the next four years would improve information collected about Kiwi families, helping to create a clearer picture when it came to poverty, the Government said.
It would give the department enough money to increase the Household Economic Survey (HES) sample size from between 3500 and 5000 households to 20,000 households.
However the Budget did not allocate funds to remove Section 70A, which reduces the benefits of single mothers who refuse to name the father of their child.
Auckland Action Against Poverty (AAAP) co-ordinator Ricardo Menendez said the sanction was punitive.
He was disappointed the $25 million a year was not allocated to change section 70A, when $100 million was being spent on the America's Cup.
"Given Labour has previously agreed to remove Section 70A sanctions for people receiving a benefit, we were disappointed that no changes on welfare came about in [yesterday's] announcement," he said.
"Withholding money from our poorest communities and core public services doesn't align with a government that claims to be pulling out all the stops to end homelessness and child poverty."
The Government could issue a directive to Work and Income workers to assume that solo parents' motivations for not naming the father in the birth certificate are reasonable, Menendez said.
"It would be that simple."
Reaction from others in the social sector was mixed.
Children's Commissioner Judge Andrew Becroft said the Budget took children seriously.
He welcomed the focus on reducing child poverty, a critical step towards improving child wellbeing.
"The initiatives taken in this budget are important first steps."
Save the Children NZ (SCNZ) welcomed the "positive impact" they believed the Budget would have on children.
However, while Social Services Providers Aotearoa (SSPA) welcomed the Budget's focus on helping the country's most vulnerable families, they said it bypassed essential and intensive community-based child and family services which were in need of more funding.
And Te Pou Matakana chairman Merepeka Raukawa-Tait called it a "Budget of broken promises" for Whānau Ora, which did not receive any funding despite an election promise from Labour MP Kelvin Davis to increase funding by $20 million.
The announcement included nothing for Whānau Ora, despite the election promise to provide the extra $20m.