The video, promoting Momoa's new Apple TV+ show See, shows the actor putting a biscuit in his mouth and letting the kodiac brown bear take it out.
Now vegan charity PETA has blasted the actor - saying captive animals who are forced to perform are frequently mistreated by trainers.
"Momoa apparently doesn't realize that there's no behind-the-scenes justice for this exploited bear," PETA said in a statement.
"Wild animals are often torn away from their mothers as infants and thrown into a life in which trainers frequently use cruel techniques such as food deprivation, beatings, electric shocks, and chaining to force them to perform.
"Momoa knows how convincing and lifelike computer-generated imagery, animatronics, and other cutting-edge technologies are, but subjecting a bear to the bright lights and bustle of a production set is stressful and totally outdated, so we hope he'll refuse to participate in stunts involving wild animals in the future."