The American tycoon now plans to spend millions on a major refurbishment of the hotel.
Trump said: “ It is an honour and privilege to own one of golf’s greatest and most exciting properties.
“I intend to invest many millions of pounds in order to bring the hotel to the highest levels of luxury.
“When completed, I believe that the Turnberry Hotel will be the finest and most luxurious hotel in all of Europe.”
The Turnberry Resort is home to three links-style golf courses, six restaurants, a luxurious spa and a five star hotel which will continue to be managed by Starwood Hotels & Resorts.
Turnberry has hosted the Open four times – the last in 2009 when it was won by American Stewart Cink.
Trump said the iconic Chamionship course “will not in any way be touched or altered other than with the approval of the Royal & Ancient.”
Turnberry will be the Trump Organisation’s second property in Scotland alongside the Trump International Golf Links in Aberdeen.