Mr Clarke, a Whangarei local, was getting live bait for the Beach and Boat competition when the shark swam towards the 5.7m boat.
It was the first shark he had ever seen.
"Everyone in the boat was really excited.
"We didn't know what breed of shark it was until it got closer," he said.
The "curious" shark swam around the boat for about five minutes.
"It came and left and came back and left again.
"It started coming for the burley. Definitely wasn't shy," he said.
He thought the great white was about 3.5m long.
"It wasn't too scary as the boat was bigger."
Mr Clarke said he had free dived around the area before but most likely won't be doing that again for a few weeks.
"It was a bit scary knowing the shark was exactly where we were."
He said the group had spotted two bronze whaler sharks earlier that day.