Police in Canberra's north are appealing for help to find a giant fibreglass dinosaur that was stolen from outside the National Dinosaur Museum at Gold Creek.

The Utahraptor statue stands 1.6 metres tall and three metres long and is valued at $2,400.

It was taken from the Nicholls site at some stage on Thursday night.

The museum's Ben Wardle says the statue appears to have been targeted by thieves after being moved for landscaping renovations.

"We've been adding some large granite boulders, just making the garden a bit more accessible and enjoyable," Mr Wardle said.

"We'd left a couple of the life-like fibreglass dinosaurs unsecured overnight, and in the morning we discovered that one was missing.

"It is quite heavy and awkward, it would require more than one person to carry it, and it wouldn't fit in an ordinary sedan."

Mr Wardle says the museum would love the dinosaur statue to be returned.

"Even if it was just returned anonymously," he said.

"Its very popular and quite an attraction for us.

"We've got a couple of large ones by the road and they definitely bring people into the museum."

Superintendent Brett Kidner says anyone who spots the life-like dinosaur statue should call CrimeStoppers.

"Its brown in colour with dark stripes across the back," he said.

"It would probably stick out fairly obviously on a trailer or possibly someone may have put it into the back of a truck."