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
Police are appealing for help in tracing a family of six who are feared to be travelling to Syria.
A "truly despicable" thief stole from a woman while she suffered a violent epileptic seizure.
A senior health official has called for vitamin supplements for children amid warnings over a rickets 'epidemic'.