Footage of the video posted on YouTube purportedly shows the trainer, American Alexander Crispin circling repeatedly around two tigers during his act for Circo Suarez in Sonora state, before one of the animals lunged at the 35-year-old and pulled him to the ground.
Mexican news agency Notimex reported Mr Crispin suffered neck injuries from bites and scratches from the incident.
He was taken by ambulance to the Red Cross hospital Huatabampo, Sonora where he died while receiving medical care, as a result of hypovolemic shock.
The video also shows spectators fleeing the circus tent as two workers beat the tiger to free Mr Crispin, who was pinned to the ground.
It is presumed that the Bengal Tiger was killed by one of the companions of the trainer during the struggle to try to save the trainer’s life.