An Australian adviser to the Papua New Guinea Government has been found stabbed to death in his Port Moresby home, police say.

David Nicholson, 52, of Victoria, worked for the Snowy Mountains Engineering Corporation (SMEC) as an adviser for PNG's transport department, the company said.

A security guard at his Paga Hill home said a neighbour noticed Mr Nicholson's front door had been left open and called the compound's property managers.

They then made the gruesome discovery of a body stabbed in the stomach and back.

A SMEC official who worked with Mr Nicholson said he was a well-liked, respectable employee with a good reputation. She declined to comment further.

PNG police want to speak to two young men seen leaving the compound on Friday morning.

An Australian Department of Foreign Affairs and Trade (DFAT) official confirmed the death and said consular officials in Australia were providing assistance to the man's family in Australia.

"A 52-year old Australian man from Victoria was murdered in Port Moresby," a DFAT spokesman said.

"The Australian High Commission in Port Moresby is liaising with local police."

The man's employer in Port Moresby is in contact with the family in Australia and is assisting with arrangements for the repatriation of the man's body.

Australian-based SMEC is one of the world's leading engineering and development consultancies with more than 20 subsidiary and associated companies and offices in 26 countries.