An eight-year-old UK boy with autism has been filmed breaking into popstar Michael Jackson’s iconic “Thriller” dance during a seaside stroll.

The video, captured by a neighbouring store’s webcam, shows William Ryan walking along the seafront with his mother while holidaying in Cornwall, the Mirror UK reports .

Drawn by the opportunity to participate in a public “webcam challenge”, the boy prompts his mother to play the 1982 hit on her phone while he takes his mark.

William then bursts into the famous routine, twisting his head, clapping and shimmying sideways in a perfect reproduction of the famous routine while the 1982 hit plays in the background.

His dance draws the amused attention of locals, three of whom can be seen untying a boat directly behind him.

Holiday leasing firm Aspect Holidays posted the video to their Facebook page last week, congratulating William on his performance, naming him the winner of their “half-term webcam challenge”.

William has since been rewarded with a goodies hamper that includes a £25 (A$40) toy voucher as well as a package holiday to the town next February.

Mother Gemma Ryan said her son - diagnosed with autism at age five - had taught himself the “Thriller” dance after becoming enamoured with Michael Jackson two years ago.

"Even though he is a very sociable boy he struggles to communicate with people his age,” she said.

"But his dancing is the thing that gives him his stamp and his identity.”