The accident occurred around 11:15 p.m. Thursday in the area of the Quakerbridge Road overpass in Lawrence Township. Officials were still working Friday to identify the man, who was pronounced dead at the scene.
NJ Transit says the man was struck by Northeast Corridor train 7879, which had departed from New York shortly before 10 p.m. and was nearing its scheduled arrival in Trenton when the accident occurred.
There were no reports of injury among the roughly 250 passengers, who were transferred to another train to complete their journey.
Authorities temporarily closed down two of the four tracks in the area while their investigation was ongoing. That caused some travel delays.