A man had beer poured down his back, a beer can thrown at him and was verbally abused, said British Transport Police.
Officers are investigating the assault at Lancaster train station and have released a CCTV image of a man they would like to speak to.
The victim, a 31-year-old man from Morecambe, walked along platform three and was followed by a man who had also left the train.
PC Gavin Daw said: “The victim had been on the train from London to Lancaster and, during the journey, had been subjected to verbal abuse by a group of drunken men.
“When he left the train he was followed by one of the men who poured beer down his back and then threw the empty can at his back.
“Clearly this was not an incident which left the victim with serious injuries, but he was extremely intimidated by the assault and was left fearing for his safety.”
“I am confident the man pictured will have information about the incident and ask anyone who recognises him to come forward.”
The incident happened shortly after 9pm on Friday, May 23.
Call 0800 40 50 40 quoting log PSUB/B7 of 19/6/14.