Animals safe after Taronga Zoo fire

Sydney's Taronga Zoo says all its animals and staff are safe after a fire broke out at the popular tourist spot.

A resident from across the harbour spotted the fire and raised the alarm after 1am on Tuesday.

"Obviously someone is awake over there and they have looked out their window and saw the flames," NSW Fire and Rescue (NSWFR) Inspector Ron James told the Seven Network.

"They thought it was a bush alight and that was the initial call."

It's understood the fire was contained to a staff common room, which was badly damaged.

Inspector James said crews initially feared animals at the Mosman zoo were caught in the fire.

Taronga Zoo issued a statement saying no animals or people were injured.

"Preliminary investigations have found no suspicious circumstances," it said.

Fire investigators are on the scene.