The Italian TV host, who split from A-list actor Clooney earlier this year, has long been against the use of fur. Her campaign will be shown prominently in Milan, where designers are still known to use fur in their collections.
"This is a thing which I personally believe and trust in, so nobody told me to do it. Since I was a little kid, I was against fur, I never wore fur in my life," she told Reuters.
Canalis, 33, joins a long list of Hollywood celebrities who bared it all for PETA's anti-fur campaign, including Charlize Theron and Pamela Anderson.
The Italian beauty said she was moved to work on the campaign after hearing of the immense cruelty suffered by animals in the fur trade.
"If you know what happens all around the world, everyday, like, 50,000 -- more than that -- animals are killed, bludgeoned, drowned, electrocuted, skinned alive, just for vanity. That's enough I think," said Canalis.
The model is stepping away from her famous ex-boyfriend's spotlight and into her own, with an upcoming stint on U.S. reality TV show "Dancing With The Stars." Canalis is training hard with dance partner Val Chmerkovskiy, in preparation for the live show, which premieres on ABC on September 19.