The protesters cut themselves free around 10pm after City of London Police entered the cathedral, an occupy spokesman said.
He said they decided to cut themselves free after being warned by officers that they faced arrest.
They have now left the cathedral.
Some of the awareness-raising they wanted to do has been done.
The Dean has also agreed to meet them and talk.
More top news
A cheap over-the-counter painkiller taken by millions of people in Britain every day could have the hidden benefit of slowing down ageing.
Some four million Brits are expected to fly out of the UK over the festive period, along with many more using roads and railways.
Scientists believe they may have found the key to fighting HIV - and it rests in the immune system of llamas.