Chief executive Peter Alexander says he has received feedback that DNZ's management expenses are higher than for other property companies.
Mr Alexander says the company has taken care to make sure it has appropriate staff to continue business as usual, including the recently announced Westgate project.
The two senior executives leaving are investment, development and capital managment general manager Philip Brown and property general manager Patrick O'Reilly.
Mr Alexander says their departures are in no way a reflection on the calibre and dedication of the employees.