Staff in Hekia Parata's office lasted an average 4.6 months before she became a minister, newly released information shows.

The revelation raises fresh questions about Ms Parata's relationship with her staff after a departing senior private secretary laid a personal grievance complaint, and former education secretary Lesley Longstone walked away with a $425,000 payout.

Information provided by Speaker David Carter shows that, between January 2009 and November 2010, five staff worked in Ms Parata's office - with an average tenure of 4.6 months.

None of those who left underwent an exit interview, despite being offered one. One severance payment was made in the 2009-10 financial year as part of a "full and final settlement signed by the then mediation service of the Department of Labour".

Mr Carter refused to release further details about the former staff members or the payout, citing privacy implications and because, he said, it was not in the public interest.

However, in answers to written parliamentary questions, Mr Carter also confirmed that, since June 2009, there had been seven staff employed in Ms Parata's electorate office for an average tenure of 9.14 months.

Labour MP Chris Hipkins said Ms Parata needed to work on her people skills, and the latest revelations were further evidence of her poor leadership style.

"The turnover of staff working in Hekia Parata's office is alarming," he said. "A successful minister of education needs to have a wide network of collaborative, trusting relationships. Clearly Hekia Parata is incapable of developing that."

Ms Parata declined to comment.