Lily Kerr has been sacked from the Health and Social Care Board for leaking confidential documents.
Health minister Edwin Poots also removed the former trade unionist from her post as chair of the Northern Ireland Social Care Council.
Mr Poots says he sacked her because she had emailed sensitive Health and Social Care documents to third parties, understood to be the media.
Mrs Kerr is a former official of the trade union Unison and was a member of the Health and Social Care Board (HSC) since it began. The board is responsible for commissioning services.
She was appointed chair of the Social Care Council for a four-year term from December 2010. It is the regulator for social workers and other social carers in Northern Ireland.
Mr Poots said: "Non-executive members, who are appointed to boards of HSC bodies, are in positions of responsibility, and as such must demonstrate the highest standards of corporate and personal conduct based on a recognition that patients and clients come first."
Mr Poots said Mrs Kerr had been an effective board member and chair but added: "I regret that the actions of Mrs Kerr on this occasion, and for whatever reasons she had, fell short of the standards expected by those holding public office."
SDLP MLA Conall McDevitt questioned whether the minister's response was proportionate. He said: "I do think he needs to ask himself whether the dismissal, in contested circumstances, of a prominent figure in the healthcare and trade union sectors sends the right message to those who work in the sector he governs, given the other significant pressures they are facing at the moment."
The chair of the Irish Congress of Trade Unions' Northern Ireland committee, Pamela Dooley, said the singling out of Mrs Kerr for this "unfair and unjust" treatment amounted to an abuse of power by the minister.
"The alleged offence is that Ms Kerr publicised documents which were already in the public domain. There is no accusation that Ms Kerr is involved in any other leak, and she has acted with complete integrity throughout her public service," she said. "What adds to our unease about this action by the minister is that incidents of leaking are hardly new to the Northern Ireland Executive and no such sackings have occurred."