Trains running into Manchester from Wigan, Newton-le-Willows and Liverpool will be disrupted for several hours because of a fire in Salford.
The cancellations are expected to cause chaos in the evening rush hour. Fire crews fear the building could collapse onto the line.
"Unfortunately because the building and fire is right next to the railway line we have asked for the trains to be stopped and overhead line equipment isolated.
"It could be several hours before we can be confident of what will happen to the building and how the fire will develop."
More top news
Largely dry overnight. Clouding up midweek
A man who brutally murdered a woman before putting her body into a suitcase and setting fire to it has been jailed for at least 21 years.
A sobbing widow told a court she clutched her husband's hand telling him she loved him as he lay dying after being run over by car thieves.