It happened on May 7 at the Buffalo Circus in Doullens.
Dramatic video from a woman in the audience showed the lion grappling with the trainer before it was subdued, allowing the trainer to escape.
The trainer, Steeve Loberot, suffered serious injuries to his head and throat and was taken by helicopter to a hospital.
He was in surgery for several hours and is now recovering.
Representatives with the circus said that despite the vicious attack, the lion will not be euthanized.
SEE ALSO: 9-year-old girl attacked by kangaroo at the zoo
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