Mr Burns, who is currently on extended sick leave, will be replaced by Michael O'Brien who has been appointed executive director responsible for the management of Equity Trustees.
Equity Trustees chairman Tony Killen said Mr Burns initiated "many significant actions and projects for the group" during his six-year tenure, including the acquisition and integration of ANZ Trustees in 2014.
"Other substantial achievements are the corporate restructure through the establishment of a non-operating holding company ... and the creation of an executive leadership team to support and drive the group's future growth," Mr Killen said.
Mr O'Brien, 53, has been a non-executive director of Equity Trustees since 24 July 2014 and is the former chief executive of Invesco Australia and chief investment officer of AXA Australia and New Zealand.
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