A "FATTER than fat" mother of four says she's sick of fellow commuters who abuse her for being obese.

Stephanie Payne, 31, who once weighed 243kg, said she had been the victim of countless unprovoked, hurtful attacks from passengers.

Ms Payne said she caught an early train so she could have a seat without being abused.

Fellow passengers have called her a "fat pig", sometimes in front of her children.

"It happens to me all the time and up until this point I've put up with it," she said.

"When people tease me, it makes me feel isolated, like I don't have the right to catch a train."

Ms Payne said she should not be forced to buy a second ticket because she took up more room than other passengers.

She listens to music to avoid hearing the taunts from other passengers.

"I am constantly picked on and bullied for no other reason other than the fact that I am overweight," Ms Payne said.

Ms Payne now weighs 180kg after lap-band surgery and a fitness program.

Breaking point was reached last week when she was abused by commuters waiting at North Melbourne station.

Writing in her blog, she complained that mX regularly published derogatory comments about overweight people on public transport.

"It seems by them running these opinions, it has given some members of the public the idea that it's OK to attack a fat person," Ms Payne wrote.

Public Transport Minister Terry Mulder said: "People need to be conscious of the needs of their fellow passengers and treat them with basic courtesy and respect."

V/Line spokesman James Kelly said people abused by other passengers should raise the issue with the conductor.

"We would always encourage appropriate standards of behaviour from passengers to each other," Mr Kelly said.

"It's not up to other passengers to determine what right anyone else has to travel on public transport."

For more on Stephanie Payne and her frustration at being abused on public transport go to the Herald Sun.