A 45-year-old man was stabbed to death and left bleeding on a Queens sidewalk Sunday night in a bar fight that proved fatal.

The bloody brawl spilled out of Kelly’s Pub on 41st Avenue in Flushing just before 10 p.m. and left a second man with several knife wounds, police said.

The second victim, 39, was found in the doorway of the bar with six stab wounds to the back.

The fatal victim was discovered with a head wound around the corner on Main Street, according to cops.

Both men were taken to NewYork-Presbyterian Queens, where the 45-year-old was pronounced dead.

A knife was recovered from in front of the bar.

Police believe the two men may have stabbed one another, according to preliminary information gathered at the scene.