The chairman of Housing New Zealand, Alan Jackson, is resigning his role to avoid a potential conflict of interest.
Dr Jackson is also a director at Fletcher Building.
Housing Minister Nick Smith says the agency has had processes to avoid any perceived or real conflict of interest between Dr Jackson's roles.
But Dr Smith says Housing New Zealand's new work schedule includes a massive rebuild programme in Christchurch, which Fletcher Building might tender for.
He says Dr Jackson considered it untenable to continue in both roles.
Deputy chair Adrienne Young-Cooper will be acting as chair until a new one is appointed.