The Duke of York, fourth in line to the throne, set off from the 87th floor -- just below the top of the 310-metre (1,017-foot) high tower -- finishing half an hour later on level 20.
Queen Elizabeth II's second son made the descent in support of The Outward Bound Trust educational charity and the Royal Marines Charitable Trust Fund, which benefits serving and retired troops.
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One of around 40 making a descent -- including 78-year-old British mountaineering great Chris Bonington -- Andrew raised £290,000 ($460,000, 365,000 euros) in sponsorship.
"I was scared at the top," the 52-year-old prince told reporters after making the 785-foot descent.
"The most difficult bit was walking up. You've actually got to walk the last 10 floors to the top.
"And so you have a moment to realise where you are going and what you're going to do.
"The difficult bit was actually stepping out over the edge.
"The training I had done in the summer up with the Royal Marines at Arbroath (Scotland) gave me the confidence to be able to step over the edge without too much trepidation."
He said there was condensation on the upper windows, meaning he slipped down most of the first section.
Andrew is a Royal Navy commander who served in the 1982 Falklands War.
He officially launched the Shard on July 5 along with Qatari Prime Minister Hamad bin Jassem al-Thani.
The tower, close to London Bridge on the south bank of the River Thames, is designed to resemble a shard of glass. Costing £450 million to build, it was 95 percent funded by Qatar.
