The singer collected eight awards while wearing the Franc Fernandez-designed outfit, complete with boots, purse and a hat made from cuts of beef.
Cher, who presented the prizes, wrote on her Twitter account that as an "art piece it was astonishing!" and that the meat purse was "genius."
She added: "modern art elicits discussion, introspection & conflict! Everyone's talking about it! BINGO!"
However, animal rights groups condemned the garment.
A statement from People for the Ethical Treatment of Animals said that "wearing a dress made from cuts of dead cows is offensive enough to bring comment, but someone should whisper in her eat that more people are upset by butchery than are impressed by it."
Lady Gaga told chat show host Ellen DeGeneres, who had presented her with a "veggie bikini" on air, she meant no disrespect to anyone that is vegan or vegetarian, and called herself "the most judgment free human being on the earth."
"However, it has many interpretations. For me this evening, if we don’t stand up for what we believe in and if we don’t fight for our rights pretty soon, we’re going to have as much rights as the meat on own bones. And, I am not a piece of meat.”
