A female zookeeper has been attacked by a lion at a zoo on the NSW South Coast.

Emergency services were called to Shoalhaven Zoo on Friday morning after reports the woman, in her mid 30s, suffered serious face and neck injuries in the attack, a NSW Ambulance spokeswoman said.

Several ambulance crews, including a rescue helicopter, are on the scene treating the woman who is in a critical condition. NSW Police are also on the scene, a spokeswoman told AAP.

AAP