Passengers in Hampshire were treated to some colourful descriptions from the announcer, who called vandals who broke a window "muppets".
The train stopped near Southampton after vandals threw rocks at it.
Initially describing them as "individuals", the announcer became more animated as time went on.
"The service is running 10 minutes late. This is due to the train coming under attack at Southampton Airport," he told passengers at Winchester.
"Some pond life down there with the intellectual capacity of a flip-flop threw rocks at the train."
When the train reached London Waterloo, at around 7pm on Sunday, he said: "We are 11 minutes late due to the incident at Southampton Airport - where these muppets attacked the train."
The South West Trains Service was travelling between Bournemouth in Dorset and London when it was attacked.
"Individuals threw objects and rocks at the train," the announcer - who did not reveal what job he did on the train - told those on board at Southampton Airport.
"We have got a smashed window which needs repairing before we can move."
At one point the man used a "profanity" to describe the vandals, asking those on board to "forgive" him for swearing over the loudspeaker.
In a statement given to Newsbeat, South West Trains said: "We are looking into this alleged incident to establish what happened.
"Our staff are trained to keep passengers updated on issues affecting their journey.
"We would always expect this to be done in a professional manner using appropriate language."
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