The body of the man, who has not yet been identified, was found on Saturday on the railway line at Meadowhall shopping centre in Sheffield.
It had been reported that he had been struck by the Edinburgh to Penzance CrossCountry train.
So far no details have been released about how the man came to be struck by the train, or his exact location when the collision happened, but it is not believed crime was involved at this stage.
Paramedics, South Yorkshire Police and British Transport Police attended the scene, where the man was pronounced dead.
A spokesman for British Transport Police said there are not thought to be any suspicious circumstances surrounding the death.
He said: "At 15.49 hours on Saturday a report was received that the 12.05 Edinburgh to Penzance passenger train operated by CrossCountry trains had struck a person on the railway line at Meadowhall railway station, Sheffield.
"Paramedics, together with police officers from South Yorkshire and BTP, attended.
"The body of a male person was found and life was pronounced extinct at the scene.
"There are no suspicious circumstances and the coroner has been informed."
He added that a number of passengers were thought to have been on the platform at the time of the incident and they may have information to help the investigation.
Anyone who can assist is asked to contact British Transport Police on 0800 405040.