Missing Qld father may have been murdered

A father's mysterious disappearance in the Gold Coast hinterland is being treated as a suspected murder.

Gregory John Dufty was last seen on July 6, when police believe he parked at a seafood restaurant, before being taken to the dead-end Nathan Homestead Road, at Mt Nathan, in a Mack truck.

"We believe at Nathan Homestead Road he got into another vehicle and that's the last sighting as such," Detective Superintendent Dave Hutchinson said.

Police are now proceeding with a homicide investigation, with Det Supt Hutchinson saying there is no evidence showing the 37-year-old is still alive.

The pool builder's family baffled by his disappearance, with Mr Dufty's mother, Margaret, and ex-partner, Shani Mill, making an emotional plea for information about his whereabouts.

"He's my eldest son, I love him," Mrs Duffy said on Friday, choking back tears.

"He has a beautiful heart, he loves his children, he loves Shani, he loves his family.

"Someone must know something. We are asking they come forward with information."

Ms Mill said Mr Dufty was a "good dad".

"He definitely wouldn't have been going (to the restaurant) to eat, he doesn't like seafood," she said.

Police are keen to speak to anyone who may have seen a Mack Truck or anything suspicious in the Mt Nathan or Maudsland area that night.