Mystery surrounds two men found dead on drifting boat off coast of Queensland

Police have launched an investigation after discovering the bodies of two men on board a boat found drifting in waters off Queensland's coast.

A 39-year-old from Emerald and a 59-year-old from Mackay, believed to be his father-in-law, were on a fishing trip on a six-metre aluminium catamaran when disaster struck.

Another boat came across the vessel near the mouth of Island Head Creek at Shoalwater, near Yeppoon on the central Queensland coast, at about 11.30pm on Friday.

The skipper contacted water police who attended and found the men deceased on board.

It appears the boat was involved in some kind of collision at high speed, with "significant damage to the front, below the water line", Queensland Police said in a statement.

Shaun Halson from Queensland Water Police told reporters that the area is characterised by "lots of small, rocky islands and submerged objects".

While the weather was fine last night, the sky was darkened by thick smoke from bushfires.

"While (the collision) was at speed, there's nothing to suggest that speed was excessive," he said.

The two men appear to have died in the collision, initial inquiries indicate. The pair were the only passengers on board.

"A passing sailing vessel had observed a motor vessel, which appeared to be in difficulty but they were unable to assist at that time."

The Sailfish 3000, a six-metre aluminium catamaran, suffered significant damage to the front, below the water line, police said.

Investigations are continuing.