Ministry of Education chief executive Karen Sewell will retire at the end of July after a 45-year career.
"It has been immensely satisfying to have served young New Zealanders all my adult life," she said today.
"I have also considered it a great privilege to be a public servant."
Ms Sewell, who was also Secretary for Education, said New Zealand delivered a world class education system for most students.
"The challenge for the future is to lift achievement for every student, particularly Maori and Pasifika students, and students with special needs."
Before heading the ministry Ms Sewell was chief executive and chief review officer for the Education Review Office.
The New Zealand Qualification Authority (NZQA) asked her to act as its chief executive during difficult period for the organisation in 2005.
While there, Ms Sewell developed processes said to have led to more consistent results for NCEA.
She has taught at schools in New Zealand and Britain, including Onslow College in Wellington, and was principal of Green Bay High School in Auckland.
In a statement this morning, Education Minister Anne Tolley thanked Ms Sewell for her work in the sector.
"Karen has dedicated her life to education, and deserves praise for her hard work in lifting the achievement levels of students in New Zealand," Mrs Tolley said.
"I have appreciated being able to call upon her advice and expertise, during a time of significant change, on a whole range of priority areas for the Government in education."
