A squid as long as a bus has washed up on a beach on the west coast of Tasmania.

Measuring eight metres from the tip of its body to the end of its tentacles, the squid weighs about 250 kilograms.

This giant squid washed up onto Ocean Beach in Strahan, the first known such stranding off Tasmania's west coast.
(Tasmania Parks and Wildlife Service/Associated Press)

The giant squid was found by a beachcomber Tuesday in Tasmania and was to be taken to the Tasmanian Museum for testing and possible display. Zoology experts from the museum are hoping to determine its age and how it died.

The museum's senior curator of Antarctic and southern oceans, David Pemberton, says squid live off the west coast and feed on blue grenadier, a cod-like fish.

"The only strandings on beaches we ever had were in the east and south-east of [Tasmania] and to me this one's intriguing because it's turned up on our west coast," he said.

"It's the first record that I know of one on a beach off the west coast."

With files from the Australian Broadcasting Corporation