The officer was spotted getting into the spirit of the Notting Hill Carnival, an annual event celebrating Britain's West Indian community, by an MC on stage.
"We got a policeman over there with some moves," the MC says.
"Make some noise for the undercover raver."
Twitter user @phemmynice shared a video of the officer's antics, and he was quickly identified as Police Constable Dan Graham.
The officer, from Kingston in London's south-west was dubbed 'Dancing Dan' after appearing on Britain's Got Talent earlier this year.