Sharks are invariably a part of the sea in Australia, but this encounter was a bit too close for one family.

Jodie Brown was on a boat with her family of seven on Tuesday near the town of Port Victoria in South Australia, when a great white shark estimated to be five metres long began to circle them.

"It just swam up to the boat from behind and it was just circling us for about 20 minutes, it would just go round and come back again," Brown told The Advertiser.

“We had to leave in the end to take two girls back to shore because they were freaked out, but the whole time it was just amazing."

Brown told the newspaper the shark might've been attracted by the fish they were catching from the boat.

In a video, people were told to stand away from the edge of the vessel, which measured 6 metres long -- only slightly larger than the shark.

View this post on Instagram

"We were all in shock really because of the size and width of it ... it was an incredible experience because it's not often you're in the presence of something bigger and more powerful than yourself," Gemma Brown told Sunriseon Thursday.

Unfortunately the shark's appearance meant that swimming plans were put off, but it's certainly a freaky confrontation you won't see everyday.