The 30-year-old fan, who was thought to have been hit on the head with a bin, was found unconscious. He was taken to hospital where he later died.
A 25-year-old man from Preston has been arrested over the incident.
Staffordshire Police said the injured man was initially treated at the scene for a head injury and cardiac arrest by staff from West Midlands Ambulance Service and St John Ambulance.
The fan was resuscitated at the scene and then taken to hospital.
A police spokesman said: "A 30-year-old man was pronounced dead at 1.55am this morning at University Hospital North Staffordshire.
"The circumstances are being fully investigated and a 25-year-old man remains in custody and is helping police with their inquiries."
Ch Insp Adrian Roberts, match commander at the game which saw Stoke beat Blackburn Rovers 3-0, said there were just over 1,300 Blackburn fans at the game, and no Stoke fans were involved in the incident.
Source: BBC Sport
Source: BBC Sport