A spear fisherman has filmed the terrifying moment he came face-to-face with a massive great white shark off the NSW Coast.

Tim Knight admits he was scared but says he would have spent the rest of his life kicking himself, if he had not taken the brave plunge.

After a few last words, he plunged into the water off Bateman's Bay and came up close with a great white shark.

Mr Knight was hanging off the back of a five-metre boat that was about the same size as the monster in front of him.

View photos Tim Knight got up close and personal to film the shark. Photo: 7 News More

The great white seems quite calm, unlike the humans above - who hadn't expected the creature to be as big as it was.

"I though he was smaller. I looked at him and went...that ####'s big."

This was no accidental meeting.

View photos In the water, looking back at the boat, Tim Knight put himself in a precarious position to capture footage of a great white. Photo: 7 News More

"I've always said, if I can find one in clear water I'll jump in, I've got to just jump in and see it for myself," said Mr Knight.

He was spearfishing nearby when the opportunity arose and a great white was nosing around some fishing boats about 17kms offshore.

"The fishing boats want to catch a nice big game fish like a kingfish, or a dolphinfish, and the sharks want the same thing so not surprising to see them in a similar area," Amy Wilkes from Sealife Sydney Aquarium said.

But it is surprising to see a fisherman get so close.

View photos Tim Knight admits he was scared but says he would have spent the rest of his life kicking himself, if he had not taken the brave plunge. Photo: 7 News More

"She didn't mind us in her environment, just gave us the little extra push I needed just to jump in the water and get the footage of this amazing animal," Mr Knight said.

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