Jim Sheridan, Labour MP for Paisley and Renfrewshire North, said Mr Cameron should say sorry as the man subjected to the Prime Minister's accusation, Stevie Deans, has been cleared of all allegations against him.
The premier claimed last year Mr Deans was a "rogue" operator, who nearly brought the Scottish petrochemical industry to its "knees" in the Grangemouth refinery industrial dispute.
Mr Deans had been suspended while the site's owner, Ineos, probed his involvement in a row over the selection of a Labour Party candidate in Falkirk.
Management were said to be looking at claims he used company time for union business in his role with Unite. The treatment of Mr Deans, who resigned from his job and union role, led to a strike action and temporary shutdown of the plant.
Mr Sheridan told Commons Leader Andrew Lansley: "The Prime Minister from the despatch box described the then-Unite union convenor, Stevie Deans, as a rogue."
He added: "Mr Deans has been cleared of all allegations levelled against him. Could you therefore arrange for the Prime Minister to come back to the despatch box and apologise to Mr Deans and his family?"
Mr Lansley said: "Perhaps in the first instance the Labour Party would like to publish their own internal report relating to the events in Falkirk and then we will see where we go from there."