The star, who is famous for getting up to mischief on his MTV show and movies, was taken into police custody at the festival for an apparent off-camera incident.
He later claimed that he was accosted for swimming with his clothes on.
The 32-year-old was spotted handcuffed and being taken in by officers after a party got out of hand, reports TMZ.
He was seen being whisked away in drenched clothing by three men in the American state's French Quarter.
Margera has since said: "Yeah, I was swimming in a pool with my clothes on at Mardi Gras. Not really a good story ... but that's what happened."
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