Shortly before midnight on Saturday, 28 November police received calls from concerned residents about a large gathering taken place in a garage area at Marlings Park Avenue, Chislehurst.
Officers attended and found in the region of 60-80 people present.
On the direction of officers one group immediately left the premises, but a second group was found hiding in a room; they were all peacefully dispersed by officers.
The organiser of the event, a 35-year-old man, was located and advised that enforcement action would be taken.
He now faces a possible £10,000 fine under the Coronavirus regulations.
Chief Inspector Neil Jeffs of the South Area Basic Command Unit said: “This was a blatant attempt to breach the Coronavirus regulations and the behaviour of the organiser in this instance was unacceptable.
“While some of the crowd left immediately, others tried to hide in a room in a forlorn attempt to evade officers.
We will continue to take tough action against those who selfishly fail to respect the regulations which the majority of Londoners have followed admirably.”