A Melbourne commuter says she was threatened with a fine and abused by ticket inspectors for offering to pay a homeless man's tram fare.

Emily Day was riding a Route 11 tram from West Preston on Monday morning when four ticket inspectors approached a homeless man in a seat nearby.

"He [the homeless man] was not in a great place and was struggling," Ms Day said. "He did not need that and they had zero sensitivity."

"He was sitting quietly on the tram, shrinking into himself and they were just standing over him. It was really rough.