UK man with autism missing in Melbourne

Benjamin Wyatt

The father of an autistic man who disappeared from a Melbourne beach while on holiday has pleaded for the public's help to find his son.

Benjamin Wyatt, 34 and from the UK, was last seen at Half Moon Bay in Black Rock in the city's southeast on Tuesday afternoon.

His family left him in the car park to take photos but said Mr Wyatt was gone when they returned a short time later.

An extensive air, ground and water search has entered its second day while Mr Wyatt's father Phil says it's unlike his son to wander off in a strange place.

"Please, please, please if anybody sights him, get in contact with the police," he told 3AW on Wednesday.

"I think he'd probably keep walking until he finds something he recognised but that's obviously not going to happen because we've never been here before."

Mr Wyatt was wearing an Airlie Beach rafting sweatshirt.

© AAP 2017 Image credit: AAP Image/ Victoria Police