Platinum Asset Management announced in a statement that Mr Trumper would be joining the board as a non-executive director from 1 August.
Mr Trumper is currently the chair for NRMA and has been an adviser for data and analytics firm Quantium for more than 9 years.
He has also served on the advisory board of Wholesale Investor and as a director for Communications For Commerce for nearly a decade.
Mr Trumper has had further board experience spanning the sectors of artificial intelligence, data, digital transformation, transport, and media.
Between 2002 and 2005, he was the chief executive of Time Inc.