The unnamed employee at the Kaliningrad Zoo in Russia was badly mauled but was rushed to hospital is expected to survive.
Alarming pictures show the woman on the back on the ground with the tiger on top of her seemingly going for the kill.
The commotion alerted other visitors who ran to join the hero onlookers saving the woman who was able to run to a secure part of the compound.
“The girl’s face face was bleeding,” said one account based on the accounts of witnesses.
“She screamed and tried to fight off the animal.”
Other zoo employees were not present at the moment of the surprise attack, and it was down to the Russian visitors to save the keeper.
The Siberian tiger – the largest cat in the world – was supposed to be contained in another part of its compound when the woman brought its food.
Culled: The UK Mirror