Andrew Katos, the Liberal MP who represents the electorate of South Barwon, has also accused the premier of mocking Opposition Leader Matthew Guy over his height.

A day after Labor front bencher Wade Noonan returned to work after battling a mental health issue, Mr Katos said he had struggled with weight issues his whole life, and Mr Andrews' comment had made him feel "awful".

"I know I'm a big guy, and I've had problems with my weight," Mr Katos told Fairfax Media. "I've had that all my life. It is something that has always played on my mind and at times has got me down in the dumps."

Mr Katos claims to have asked a serious question about crime in his electorate, to which Labor MPs were heard to interject: "We didn't see that coming".

At this point, Mr Katos said Mr Andrews chipped in and said: "First time anyone has said they didn't see him coming".

Mr Andrews' office offered no response to the claims before deadline.

Mr Guy said anti-bullying programs in schools to teach kids to respect everyone were important but were undermined when the premier himself makes personal comments about another MP's weight.

Parliament can be a robust environment, but generally personalised attacks are seen as out of line.

Mr Guy himself drew fire this week for sarcastically saying members of Melbourne's Apex gang would be "quaking" following the appointment of Lisa Neville as Police Minister.

Labor MPs were quick to accuse Mr Guy of misogyny, while Mr Andrews said the opposition leader's  comments did him no credit.

Mr Katos said Mr Guy has also been the butt of Mr Andrews' personal attacks, claiming the premier repeatedly referred to him as a "you little man".

"That's the sort of thing you expect from a school yard bully not the premier," he said.  "You don't expect that from the leader of the state. He is the premier of this state who is preaching about tolerance and equality and all manner of things in that vein, and yet he comes out and says comments like that."