There's a warning to Auckland boaties following confirmation a great white shark is prowling the inner Waitemata Harbour.

The Department of Conservation says the four and a half metre shark was spotted by a family on Monday.

DOC marine scientist Clinton Duffy says there aren't many sightings of the sharks in that part of the harbour.

He says it was seen close to Point Chevalier - a popular area for kitesurfing and fishing, so people should take care in the area.

Clinton Duffy says fishers in the harbour should avoid tying burly bags to their anchor chain, as the shark is big enough to tow a small dinghy.