"When I was first on-scene, it was a little bit daunting", a paramedic told 7 News, remarking on being in a literal "lion's den" during the rescue.
Faye Stockmen, duty operations manager at NSW Ambulance, said the operation was "harrowing".
Police and several ambulance crews were on scene, treating the woman for bites and lacerations before airlifting her to a nearby hospital in critical condition.
"It is an incredibly risky situation, both for the patient and the paramedics", Stockmen said, reports 9 News.
"We literally had to walk into a lion's den", she said.
The senior zookeeper was later found unconscious by two colleagues, with injuries to her neck and head.
Shoalhaven Zoo has been contacted for comment.
Emergency services were called to Shoalhaven Zoo north of Sydney on Friday morning.
"I'll take this chance to commend the 2 zoo workers that reacted to the incident and have been capable of safe the lions and help their colleague", he instructed reporters in Nowra.
SafeWork NSW has been notified of the incident.
The family-owned zoo has been closed to the general public for the reason that begin of the coronavirus pandemic.
'We worth our employees and it has been coronary heart wrenching to face down some employees. "Thank you for all your support and we look forward to seeing you all back at the zoo soon".
"Come nose to nose with our Roarsome Foursome and get to feed the 'King of the Savannah",' the web site reads.
It's the first animal attack in a zoo since 2014 when a male handler was dragged by a crocodile and suffered minor hand injuries.