Dr Hon has launched companies in Britain and Hong Kong and is behind a holding company – The Hon Organisation – based in the tax haven of Vanuatu.
He has reportedly turned to members of the Royal family in recent years in the hope they can help raise his profile to potential investors in the Far East.
Dr Hon, 47, said on Friday evening her main role in the directorship was “to introduce a few people to me in Hong Kong”.
The tycoon, who was educated at Uppingham School and Cambridge University, told The Daily Mail that members of the Royal Family were brought on board “because of what they can do for individual projects”.
The revelations have raised questions about the way Royals who do not take the taxpayer funded Sovereign Grant manage to pay for themselves.
The Duchess of York, 59, was a non-executive director of Dr Hon’s Global Group Entertainment Limited until October last year, on a salary of £72,000 a year.
She was said to have “introduced various strategic relationships” with Dr Hon.
She is also a director of British media investment firm Gate Ventures, formerly chaired by Dr Hon, which was removed from the London junior stock exchange in 2015 after a number of Chinese investors came on board and caused the share price to rise 1,500 per cent.