NHL Star Milan Lucic -- Bar Brawl in Vancouver ... 'Do You Know Who You're F**kin' With?'

Boston Bruins star Milan Lucic dropped the gloves outside the rink last night ... brawling late night on the streets of Vancouver, and the whole thing was caught on tape.

It all went down around 4 AM outside The Queen's Republic on Granville St. -- where Milan was filmed trading blows with some random Canuck ... and Milan repeatedly asks him, "Do you know who you're f***n' with?"

Vancouver PD tells us ... some cops on foot patrol were able to break up the fight. They talked to both men but no arrests were made and no criminal charges were filed.

Milan's opponent appeared to suffer a busted lip ... but other than that, no harm no foul.

***WARNING: VIDEO CONTAINS EXPLICIT LANGUAGE***