A giant squid washed up on the South Coast of Wellington on Sunday morning.

A 4.5-metre-long squid has washed up on Wellington's South coast.

A number of people have reported seeing the huge cephalopod on Sunday morning.

A Department of Conservation spokesman said it was almost certainly a giant squid (Architeuthis dux).

They did wash up from time to time, he said. "It's not common but it's not rare."

It washed up two bays up from Sinclair Head.

Only a four-wheel drive could reach the area but the gate was locked, so the general public would likely not encounter it, he said.

At about four metres, there was no merit in keeping it to see what was going on.

He expected it would disappear with the high tide.

Passer-by Laurie Emeny measured the squid and said it was 4.5m.

"It's all in one piece, it's in great nick but I didn't see the eyes."

Many years ago, he had seen another large squid washed up on a nearby beach.

Paul Harker came across the "freshly" washed up squid about 9am.

It was located about 40 minutes past Devil's Gate, he said.