The first-in-line to the throne, whose history with Robin dated years back, gave a statement to Press Association.
"I greatly enjoyed meeting him on several occasions and his irreplaceable contribution to life will be greatly missed by countless people, including myself," said Charles.
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Robin Williams and Prince Charles pictured at the royal's charity event in 2008
He added: "He was a remarkable man, whose wonderful frenetic humour brought a special kind of laughter into people's lives."
Robin, who passed away from a suspected suicide in his California home at the age of 63, was last pictured meeting the Queen's eldest child in 2008.
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The stand-up comedian and Academy Award-winning star proved quite a hit with Charles, as the Prince was caught bursting out in laughter mid-conversation.
Prince Harry jokes around with stand-up comedian Robin Williams at his father's event
The pair were chatting backstage at the Wimbledon Theatre after a charity performance in aid of Charles' organisation, The Prince's Trust, where they were joined by other celebrities including Joan Rivers.
Princess Diana and her sons William and Harry meet Robin Williams at the 1992 Hook premiere, in which the late actor played an adult Peter Pan
This was not the first time that Harry, 29, had met the talented Chicago-born actor.
The red-haired royal was lucky enough to attend the Leicester Square film premiere of Hook with his late mother Diana, Princess of Wales and his older brother Prince William in 1992. Robin had starred as an adult Peter Pan in the children's classic.
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It's a little princess!