Bieber, 19, appears to have moved on from Selena Gomez and was seen laughing and joking with the allegedly newly-single Cyrus at Beacher's Madhouse at the Roosevelt Hotel here, reported TMZ online.
The 'Baby' hitmaker performed at the swanky venue and then headed for Cyrus' table.
Cyrus, who is said to have parted ways with her fiance Liam Hemsworth last month, hung out with Bieber for around 15 minutes before they were caught on camera leaving together.
The duo are rumoured to be planning a musical collaboration together.