Bernhard, who headed the Dutch military at the end of World War II (search), was diagnosed with incurable cancer in mid-November and tumors spread quickly to his stomach and lungs.
He died Wednesday after being moved to Utrecht University Medical Hospital, the Royal House said in a statement.
Bernhard's remains were later returned to his home at the royal palace in Soestdijk, which he shared for six decades with his wife, the former Queen Juliana, who died this year.
"Prince Bernhard was a man who enjoyed life, a vital man who remained active until a very old age," Prime Minister Jan Peter Balkenende said in a nationally televised address. "He devoted himself to issues and people close to his heart."
During the Nazi occupation, Bernhard was the top aide in Queen Wilhelmina's exiled government in London, and was reputed to have flown combat missions as a pilot. He also raised funds to help rebuild the devastated country after the war. But his image was tarnished by a bribery scandal in the 1970s and by his openly rocky marriage and affairs.
Bernhard was a dapper dresser, with glasses and a trademark carnation in his buttonhole, an avuncular presence in his adopted country throughout the second half of the 20th century.
Outside the Netherlands, he was seen as a jet-setting ambassador. He helped found the World Wildlife Fund in 1961 and became its first president, and is credited with establishing the Bilderberg group — a secretive annual discussion forum for prominent politicians, thinkers and businessmen — which he chaired from 1954 to 1976.
Regular broadcasts on Dutch television and radio were interrupted for the announcement of his death. The Dutch national anthem was played in his honor.
Bernhard was born Bernhard von Lippe-Biesterfeld, of impoverished German nobility, at Jena on June 29, 1911.
In 1995, researchers found documents in the U.S. National Archives that said Bernhard was a member of the Nazi party from 1933 to 1937, when he married Juliana.
In an open letter earlier this year, Bernhard dismissed rumors that he had any contact with Nazis during the war as "nonsense." The rumors were also rejected by both the Dutch government and the respected Netherlands Institute for War Documentation.
But Bernhard said "wasn't in a position" to deny having an illegitimate daughter in Paris.
He also accepted the findings of a government inquiry, which said he received $100,000 in improper commissions from American aircraft builder Lockheed in 1976.
"I look back with satisfaction on my life," he wrote. "I'm sure this [letter] will provoke new reactions, but frankly, I don't give a damn."
He is survived by four daughters and more than 20 grandchildren and great grandchildren.