A motorcyclist was killed on the West Side Highway early yesterday when he was rear-ended by a hit-and-run motorist and run over by a drunken driver.

Kastriot Prelaj, 22, was northbound on 12th Avenue at 4:20 a.m. when a white Honda sent him flying onto the West 46th Street asphalt, cops said.

Seconds later, a boozed-up Eliyyas Northern, also 22, of Rockland County, ran him over, police said.