The Wrecking Ball hitmaker donned a silver wig at her Art Basel show at the Raleigh Hotel in Miami and told the assembled crowd - which included her boyfriend Patrick Schwarzenegger and party organiser Tommy Hilfiger - she was breaking her usual rules for show day.
She said: "Usually I don't smoke weed and drink, well that's a lie ... usually I don't smoke weed and drink on show days, but I felt like it was fine in Miami."
Elsewhere during the show - which was largely formed of covers from artists including Led Zeppelin and Johnny Cash - Miley, 22, said she had been in a "dark place" followed by the death of her beloved dog Floyd in April and said his passing had been a "wake up call" as to how meaningless some of the things she had been doing were.
Before singing a song called Twinkle, which was inspired by a friend's dead cat speaking to her in a dream, she added: "This year has constantly challenged me, and that's why I started doing art."
The Party in the USA singer was later joined on stage by Flaming Lips frontman Wayne Coyne, and the pair dressed as a giant rainbow to sing the Beatles' Lucy in the Sky with Diamonds flanked by people dressed in shark costumes, one as a giant mushroom and another man dressed as a penis with silver streamers.
Miley ended the show by pulling back her top to reveal the silver nipple pasties as fake five dollar bills bearing her face fell into the crowd.
As she left the stage, a giant silver balloon saying ''Fuck yeah Art Basel'' was released.