Departing Treasury boss Gabriel Makhlouf will be replaced by a "world-class economist" and former New South Wales Treasury Deputy Secretary Dr Caralee McLiesh.
Makhlouf – who has been the subject of a State Services Commission (SSC) inquiry into the Budget leak and whether Makhlouf misled the Government – finished his tenure in the job on Thursday.
The results of the SSC inquiry are expected to be announced before his final day.
McLiesh, an Australian, will take over as Treasury Secretary in mid-September.
She will be the first woman to lead the Treasury in New Zealand's history.
She has more than 20 years experience in the government, international, not-for-profit, and commercial sectors.
State Services Commissioner Peter Hughes said McLiesh and has led large, complex reforms with multiple stakeholders to improve citizen outcomes.
"I have no doubt the public service and New Zealand will benefit from her skills and experience."
Hughes said McLiesh was a highly respected, world-class economist with very strong fiscal, economic policy and financial management credentials.
She is currently managing director at Technical and Further Education where she leads an organisation of about 17,000 people with a budget of AUD$1.8 billion.
Before that, McLiesh worked at the NSW Treasury in several Deputy Secretary roles from 2008-2018.
During her time at the NSW Treasury, she led the development of State Budgets, covering AUS$80 billion operating expenditure and AUS$350 billion in assets.
He job also include providing advice to the Treasurer – NSW's equivalent of the Minister of Finance – and government agencies on fiscal and economic policy.
She also helped with the coordination of the Budget and state sector accounts, taxation, intergovernmental relations and balance sheet management.
McLiesh has also worked at the World Bank and has authored, and co-authored a number of key economic reports, such as the World Development Report in 2002.
"This is a big and important role for New Zealand and the Public Service," Hughes said.