Police and Ealing Council park rangers visited the site on Friday morning (December 8) to issue the travellers with a code of conduct, the force tweeted from its @MPSEalingCommon account.
The photo shows officers and rangers approaching the site of at least four caravans, several vans, an SUV and a pick-up truck.
The parked vehicles can be seen standing on a lawn in front of a row of trees and houses.
Met Police said it will continue to monitor the area.
In the tweet the force wrote: "Earlier today, team and @EalingCouncil Park Rangers went to #ealingcommon to account travellers and issue them with the Code of Conduct.
"All recorded on Body Worn Cameras and added to the record.
"[The] team will continue to monitor area."
Police previously dispersed an unauthorised traveller camp from Ealing Common in August.
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