The visitor was apparently seen climbing into the big cat enclosure at Ningbo Younger Zoo, in the eastern province of Zhejiang, and walking towards the animals as they were feeding.
Video shows the man being pinned to the ground by one of the tigers, which seems to have its jaws clapmed round the man's head and neck.
He can be seen kicking his legs in desperation as another tiger approaches and begins to attack.
He then reportedly lay motionless as he was dragged further into the tiger's lair by his foot.
The man is set upon by tigers
Zookeepers are said to have used firecrackers and water canons in an attempt to frighten the tigers away.
But after that failed, one of the tigers was reportedly shot dead, before zoo workers retrieved the man from the enclosure and he was taken to hospital.
His condition is unclear, with some news outlets claiming the man was still being treated for his injuries, and others, inlcuding the South China Morning Post, saying he had died.
The zoo was evacuated following the attack.
One witness told the South China Morning Post: “I saw the tiger mauling the person, whose face was covered with blood.
"Every time he sat up, the tiger pushed him down again.”
The man's ordeal was said to have lasted an hour before he was rescued.
The victim has not been identified.