The accident involving the westbound nonpassenger train happened shortly after 4 p.m., at the crossing on Islip Avenue in Central Islip. Service was disrupted between Ronkonkoma and Farmingdale for a couple of hours.
The driver and sole occupant of the car, identified only as a 63-year-old man, was taken to Southside Hospital in Bay Shore and was pronounced dead a short time later, said LIRR spokesman Sal Arena.
No other injuries were reported. The crash happened at the first crossing east of the Brentwood station, Arena said.
Arena said it was too early to tell whether safety gates were up or down at the time of the accident.