The vet had received numerous death threats and hate mail from animal lovers after he shared his snaps on Instagram last year.
But he died on Saturday while hunting wild birds with friends in the Soana Valley in the Gran Paradiso National Park in north west Italy.
According to Italian reports the accident occurred at an altitude of 2,200 meters in the valley of the Colle delle Oche, above the town of Pianprato, when Ponzetto slipped and fell.
An Italian police spokesman told the Sun: "We were called by the mountain rescue services who had been alerted to the incident by someone who was out with him.
"It looks like he slipped and fell when he was out hunting.
"He died instantly and there was nothing that could be done."
The man's body was eventually recovered and taken to a hospital by helicopter.
Mr Ponzetto was forced to defend himself after the uproar following his lion photograph last year, saying: "I have the utmost respect for the animals and I have committed no offense either administrative or [through] professional conduct"
On hearing of his death however, many animal lovers claimed 'karma' had been at play.
One woman wrote: "Luciano Ponzetto,who posed with lion he killed, has died after plummeting down a ravine, while shooting birds, Devine intervention, karma"
And another added: "What goes around comes around #karma #lucianoponzetto"